Page 1
1
UPSC 2022 - CSAT SOLUTION
Directions for the following 3 (three) items:
Read the following two passages and answer the items that follow the passages. Your answers to these
items should be based on the passages only.
Passage –1
The main threat to maintaining progress in human development comes from the increasingly evident
unsustainability of production and consumption patterns. Current production models rely heavily on
fossil fuels. We now know that this is unsustainable because the resources are finite. The close link
between economic growth and greenhouse gas emissions needs to be served for human development to
become truly sustainable. Some developed countries have begun to alleviate the worst effects by
expanding recycling and investing in public transport and infrastructure. But most developing countries
are hampered by the high costs and low availability of clean energy sources. Developed countries need
to support developing countries' transition to sustainable human development.
Q.1. Unsustainability in production pattern is due to which of the following?
1. Heavy dependence on fossil fuels
2. Limited availability of resources
3. Expansion of recycling
Select the correct answer using the code given below.
(a) 1 and 2 only
(b) 2 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer: (a)
Statement 1 is correct: The passage directly mentions, “the increasingly evident unsustainability of
production and consumption patterns. Current production models rely heavily on fossil fuels.”.
Therefore, heavy dependence on fossil fuels is a reason, as per the author, for the unsustainability of
production patterns.
Statement 2 is correct: Again, the author directly states, “the increasingly evident unsustainability of
production and consumption patterns. Current production models rely heavily on fossil fuels. We now
know that this is unsustainable because the resources are finite. “. Therefore, this statement is correct
as well.
Statement 3 is incorrect: The passage states that “Some developed countries have begun to alleviate
the worst effects by expanding recycling”. This means that some countries are trying to reduce the
effects of unsustainable production via recycling and other methods. Therefore, recycling would reduce
the unsustainability in production patterns rather than aggravate it.
Page 2
1
UPSC 2022 - CSAT SOLUTION
Directions for the following 3 (three) items:
Read the following two passages and answer the items that follow the passages. Your answers to these
items should be based on the passages only.
Passage –1
The main threat to maintaining progress in human development comes from the increasingly evident
unsustainability of production and consumption patterns. Current production models rely heavily on
fossil fuels. We now know that this is unsustainable because the resources are finite. The close link
between economic growth and greenhouse gas emissions needs to be served for human development to
become truly sustainable. Some developed countries have begun to alleviate the worst effects by
expanding recycling and investing in public transport and infrastructure. But most developing countries
are hampered by the high costs and low availability of clean energy sources. Developed countries need
to support developing countries' transition to sustainable human development.
Q.1. Unsustainability in production pattern is due to which of the following?
1. Heavy dependence on fossil fuels
2. Limited availability of resources
3. Expansion of recycling
Select the correct answer using the code given below.
(a) 1 and 2 only
(b) 2 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer: (a)
Statement 1 is correct: The passage directly mentions, “the increasingly evident unsustainability of
production and consumption patterns. Current production models rely heavily on fossil fuels.”.
Therefore, heavy dependence on fossil fuels is a reason, as per the author, for the unsustainability of
production patterns.
Statement 2 is correct: Again, the author directly states, “the increasingly evident unsustainability of
production and consumption patterns. Current production models rely heavily on fossil fuels. We now
know that this is unsustainable because the resources are finite. “. Therefore, this statement is correct
as well.
Statement 3 is incorrect: The passage states that “Some developed countries have begun to alleviate
the worst effects by expanding recycling”. This means that some countries are trying to reduce the
effects of unsustainable production via recycling and other methods. Therefore, recycling would reduce
the unsustainability in production patterns rather than aggravate it.
2
Q.2. Consider the following statements:
Developed countries can support developing countries' transition to sustainable human
development by
1. making clean energy sources available at low cost
2. providing loans for improving their public transport at nominal interest rates
3. encouraging them to change their production and consumption patterns
Which of the statements given above is/are correct?
(a) 1 only
(b) 1 and 2 only
(c) 2 and 3 only
(d) 1, 2 and 3
Answer: (a/d)
Statement 1 is correct: The author mentions high costs and low availability of clean energy sources.
Immediately after that, he states that “Developed countries need to support developing countries'
transition to sustainable human development”. Therefore, the first statement is correct and it directly
follows the assertion made.
Explanation for Statement 2: Whether this statement is correct or incorrect depends upon whether we
opt for a narrow or broader interpretation of the passage. The passage mentions, “But most developing
countries are hampered by the high costs and low availability of clean energy sources.” Therefore, it
seems that the author is only focussing on issues related to high costs and low availability of clean
energy sources as hindrances for developed countries in transitioning towards sustainable human
development.
However, (taking a broader view) the question does mention “can”- and providing loans for improving
their public transport at nominal interest rates is certainly one way where developed countries can help
developing countries especially to alleviate the worst effects of unsustainable development.
Explanation for Statement 3: Likewise, this statement would be incorrect if we take a narrow
interpretation of the passage, as it specifically mentions high costs and low availability of clean energy
sources as hindrances for developed countries in transitioning towards sustainable human development.
But again, the question states “can” and encouragement (via finance etc.) to change production and
consumption patterns is certainly an area where developed countries could support the developing ones.
Page 3
1
UPSC 2022 - CSAT SOLUTION
Directions for the following 3 (three) items:
Read the following two passages and answer the items that follow the passages. Your answers to these
items should be based on the passages only.
Passage –1
The main threat to maintaining progress in human development comes from the increasingly evident
unsustainability of production and consumption patterns. Current production models rely heavily on
fossil fuels. We now know that this is unsustainable because the resources are finite. The close link
between economic growth and greenhouse gas emissions needs to be served for human development to
become truly sustainable. Some developed countries have begun to alleviate the worst effects by
expanding recycling and investing in public transport and infrastructure. But most developing countries
are hampered by the high costs and low availability of clean energy sources. Developed countries need
to support developing countries' transition to sustainable human development.
Q.1. Unsustainability in production pattern is due to which of the following?
1. Heavy dependence on fossil fuels
2. Limited availability of resources
3. Expansion of recycling
Select the correct answer using the code given below.
(a) 1 and 2 only
(b) 2 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer: (a)
Statement 1 is correct: The passage directly mentions, “the increasingly evident unsustainability of
production and consumption patterns. Current production models rely heavily on fossil fuels.”.
Therefore, heavy dependence on fossil fuels is a reason, as per the author, for the unsustainability of
production patterns.
Statement 2 is correct: Again, the author directly states, “the increasingly evident unsustainability of
production and consumption patterns. Current production models rely heavily on fossil fuels. We now
know that this is unsustainable because the resources are finite. “. Therefore, this statement is correct
as well.
Statement 3 is incorrect: The passage states that “Some developed countries have begun to alleviate
the worst effects by expanding recycling”. This means that some countries are trying to reduce the
effects of unsustainable production via recycling and other methods. Therefore, recycling would reduce
the unsustainability in production patterns rather than aggravate it.
2
Q.2. Consider the following statements:
Developed countries can support developing countries' transition to sustainable human
development by
1. making clean energy sources available at low cost
2. providing loans for improving their public transport at nominal interest rates
3. encouraging them to change their production and consumption patterns
Which of the statements given above is/are correct?
(a) 1 only
(b) 1 and 2 only
(c) 2 and 3 only
(d) 1, 2 and 3
Answer: (a/d)
Statement 1 is correct: The author mentions high costs and low availability of clean energy sources.
Immediately after that, he states that “Developed countries need to support developing countries'
transition to sustainable human development”. Therefore, the first statement is correct and it directly
follows the assertion made.
Explanation for Statement 2: Whether this statement is correct or incorrect depends upon whether we
opt for a narrow or broader interpretation of the passage. The passage mentions, “But most developing
countries are hampered by the high costs and low availability of clean energy sources.” Therefore, it
seems that the author is only focussing on issues related to high costs and low availability of clean
energy sources as hindrances for developed countries in transitioning towards sustainable human
development.
However, (taking a broader view) the question does mention “can”- and providing loans for improving
their public transport at nominal interest rates is certainly one way where developed countries can help
developing countries especially to alleviate the worst effects of unsustainable development.
Explanation for Statement 3: Likewise, this statement would be incorrect if we take a narrow
interpretation of the passage, as it specifically mentions high costs and low availability of clean energy
sources as hindrances for developed countries in transitioning towards sustainable human development.
But again, the question states “can” and encouragement (via finance etc.) to change production and
consumption patterns is certainly an area where developed countries could support the developing ones.
3
Passage –2
Unless the forces and tendencies which are responsible for destroying the country's environment are
checked in the near future and afforestation of denuded areas is taken up on a massive scale, the
harshness of the climatic conditions and soil erosion by wind and water will increase to such an extent
that agriculture, which is the mainstay of our people, will gradually become impossible. The desert
countries of the world and our own desert areas in Rajasthan are a grim reminder of the consequences
of large-scale deforestation. Pockets of desert-like landscape are now appearing in other parts of the
country including the Sutlej-Ganga Plains and Deccan Plateau. Where only a few decades back there
used to be lush green forests with perennial streams and springs, there is only brown earth, bare of
vegetation, without any water in the streams and springs except in the rainy season.
Q.3. According to the passage given above, deforestation and denudation will ultimately lead to
which of the following?
1. Depletion of soil resource
2. Shortage of land for the common man
3. Lack of water for cultivation
Select the correct answer using the code given below.
(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer: (c)
Statement 1 is correct: The passage mentions, “The desert countries of the world and our own desert
areas in Rajasthan are a grim reminder of the consequences of large-scale deforestation. Pockets of
desert-like landscape are now appearing in other parts of the country including the Sutlej-Ganga Plains
and Deccan Plateau. Where only a few decades back there used to be lush green forests with perennial
streams and springs, there is only brown earth, bare of vegetation, without any water in the streams and
springs except in the rainy season.”. This supports the assertion of the author that deforestation and
denudation will ultimately lead to the depletion of soil resources.
Statement 2 is incorrect: This statement goes beyond the scope of the passage. The passage nowhere
mentions anything related to the common man.
Statement 3 is correct: This is supported by the part in the passage which mentions, “the harshness of
the climatic conditions” and “Where only a few decades back there used to be lush green forests with
perennial streams and springs, there is only brown earth, bare of vegetation, without any water in the
streams and springs except in the rainy season”.
Q.4. What is the value of X in the sequence 20, 10, 10, 15, 30, 75, X?
(a) 105
(b) 120
(c) 150
(d) 225
Answer: (d)
The given series is:
20, 10, 10, 15, 30, 75, X?
The terms are decreasing in the initial half, and then they start increasing. The speed at which they
increase at the latter half suggest that multiplication may be involved.
The pattern is as follows:
20 × 0.5 = 10
10 × 1 = 10
Page 4
1
UPSC 2022 - CSAT SOLUTION
Directions for the following 3 (three) items:
Read the following two passages and answer the items that follow the passages. Your answers to these
items should be based on the passages only.
Passage –1
The main threat to maintaining progress in human development comes from the increasingly evident
unsustainability of production and consumption patterns. Current production models rely heavily on
fossil fuels. We now know that this is unsustainable because the resources are finite. The close link
between economic growth and greenhouse gas emissions needs to be served for human development to
become truly sustainable. Some developed countries have begun to alleviate the worst effects by
expanding recycling and investing in public transport and infrastructure. But most developing countries
are hampered by the high costs and low availability of clean energy sources. Developed countries need
to support developing countries' transition to sustainable human development.
Q.1. Unsustainability in production pattern is due to which of the following?
1. Heavy dependence on fossil fuels
2. Limited availability of resources
3. Expansion of recycling
Select the correct answer using the code given below.
(a) 1 and 2 only
(b) 2 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer: (a)
Statement 1 is correct: The passage directly mentions, “the increasingly evident unsustainability of
production and consumption patterns. Current production models rely heavily on fossil fuels.”.
Therefore, heavy dependence on fossil fuels is a reason, as per the author, for the unsustainability of
production patterns.
Statement 2 is correct: Again, the author directly states, “the increasingly evident unsustainability of
production and consumption patterns. Current production models rely heavily on fossil fuels. We now
know that this is unsustainable because the resources are finite. “. Therefore, this statement is correct
as well.
Statement 3 is incorrect: The passage states that “Some developed countries have begun to alleviate
the worst effects by expanding recycling”. This means that some countries are trying to reduce the
effects of unsustainable production via recycling and other methods. Therefore, recycling would reduce
the unsustainability in production patterns rather than aggravate it.
2
Q.2. Consider the following statements:
Developed countries can support developing countries' transition to sustainable human
development by
1. making clean energy sources available at low cost
2. providing loans for improving their public transport at nominal interest rates
3. encouraging them to change their production and consumption patterns
Which of the statements given above is/are correct?
(a) 1 only
(b) 1 and 2 only
(c) 2 and 3 only
(d) 1, 2 and 3
Answer: (a/d)
Statement 1 is correct: The author mentions high costs and low availability of clean energy sources.
Immediately after that, he states that “Developed countries need to support developing countries'
transition to sustainable human development”. Therefore, the first statement is correct and it directly
follows the assertion made.
Explanation for Statement 2: Whether this statement is correct or incorrect depends upon whether we
opt for a narrow or broader interpretation of the passage. The passage mentions, “But most developing
countries are hampered by the high costs and low availability of clean energy sources.” Therefore, it
seems that the author is only focussing on issues related to high costs and low availability of clean
energy sources as hindrances for developed countries in transitioning towards sustainable human
development.
However, (taking a broader view) the question does mention “can”- and providing loans for improving
their public transport at nominal interest rates is certainly one way where developed countries can help
developing countries especially to alleviate the worst effects of unsustainable development.
Explanation for Statement 3: Likewise, this statement would be incorrect if we take a narrow
interpretation of the passage, as it specifically mentions high costs and low availability of clean energy
sources as hindrances for developed countries in transitioning towards sustainable human development.
But again, the question states “can” and encouragement (via finance etc.) to change production and
consumption patterns is certainly an area where developed countries could support the developing ones.
3
Passage –2
Unless the forces and tendencies which are responsible for destroying the country's environment are
checked in the near future and afforestation of denuded areas is taken up on a massive scale, the
harshness of the climatic conditions and soil erosion by wind and water will increase to such an extent
that agriculture, which is the mainstay of our people, will gradually become impossible. The desert
countries of the world and our own desert areas in Rajasthan are a grim reminder of the consequences
of large-scale deforestation. Pockets of desert-like landscape are now appearing in other parts of the
country including the Sutlej-Ganga Plains and Deccan Plateau. Where only a few decades back there
used to be lush green forests with perennial streams and springs, there is only brown earth, bare of
vegetation, without any water in the streams and springs except in the rainy season.
Q.3. According to the passage given above, deforestation and denudation will ultimately lead to
which of the following?
1. Depletion of soil resource
2. Shortage of land for the common man
3. Lack of water for cultivation
Select the correct answer using the code given below.
(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer: (c)
Statement 1 is correct: The passage mentions, “The desert countries of the world and our own desert
areas in Rajasthan are a grim reminder of the consequences of large-scale deforestation. Pockets of
desert-like landscape are now appearing in other parts of the country including the Sutlej-Ganga Plains
and Deccan Plateau. Where only a few decades back there used to be lush green forests with perennial
streams and springs, there is only brown earth, bare of vegetation, without any water in the streams and
springs except in the rainy season.”. This supports the assertion of the author that deforestation and
denudation will ultimately lead to the depletion of soil resources.
Statement 2 is incorrect: This statement goes beyond the scope of the passage. The passage nowhere
mentions anything related to the common man.
Statement 3 is correct: This is supported by the part in the passage which mentions, “the harshness of
the climatic conditions” and “Where only a few decades back there used to be lush green forests with
perennial streams and springs, there is only brown earth, bare of vegetation, without any water in the
streams and springs except in the rainy season”.
Q.4. What is the value of X in the sequence 20, 10, 10, 15, 30, 75, X?
(a) 105
(b) 120
(c) 150
(d) 225
Answer: (d)
The given series is:
20, 10, 10, 15, 30, 75, X?
The terms are decreasing in the initial half, and then they start increasing. The speed at which they
increase at the latter half suggest that multiplication may be involved.
The pattern is as follows:
20 × 0.5 = 10
10 × 1 = 10
4
10 × 1.5 = 15
15 × 2 = 30
30 × 2.5 = 75
75 × 3 = 225
Q.5. An Identity Card has the number ABCDEFG, not necessarily in that order, where each letter
represents a distinct digit (1, 2, 4, 5, 7, 8, 9 only). The number is divisible by 9. After deleting
the first digit from the right, the resulting number is divisible by 6. After deleting two digits
from the right of original number, the resulting number is divisible by 5. After deleting three
digits from the right of original number, the resulting number is divisible by 4. After deleting
four digits from the right of original number, the resulting number is divisible by 3. After
deleting five digits from the right of original number, the resulting number is divisible by 2.
Which of the following is a possible value for the sum of the middle three digits of the number?
(a) 8
(b) 9
(c) 11
(d) 12
Answer: (a)
The number has 7 digits, and has been denoted by: ABCDEFG
These letters can be replaced by 1, 2, 4, 5, 7, 8, 9, not necessarily in the same order.
We have to find the possible value of C + D + E
The original number (ABCDEFG) is divisible by 9. It has to be as 1 + 2 + 4 + 5 + 7 + 8 + 9 = 36, which
is divisible by 9. This information is utterly useless.
After deleting 1 digit from the right, the resulting number (ABCDEF) is divisible by 6. It means that, F
= 2, 4 or 8 (i.e. an even number).
Also, if even after removing G, the remaining number is divisible by 3, then it means G = 9.
After deleting 3 digits from the right, the resulting number (ABCD) is divisible by 4. It means that, D
= 2, 4 or 8 (i.e. an even number).
After deleting 5 digits from the right, the resulting number (AB) is divisible by 2. It means that, B = 2,
4 or 8 (i.e. an even number).
So, F, D and B are even numbers (2, 4 or 8). And, A, C, E, and G are odd numbers (1, 5, 7 or 9).
After deleting 2 digits from the right, the resulting number (ABCDE) is divisible by 5. It means that, E
= 5.
So, we just have to find C + D + E = C + D + 5, which must be an even number as C is odd (1, or 7),
and D is even (2, 4, or 8).
On observing the options, we can see that C must be 1 and D must be 2. So, C + D + E = 1 + 2 + 5 = 8.
Note: This information was also redundant - After deleting 4 digits from the right, the resulting number
(ABC) is divisible by 3. But it may be useful if we want to know the entire number. The only odd
number remaining is 7. So, A = 7. So, the ABC is actually 7B1. B can be 4 or 8. But for 7B1 to be
divisible by 3, B must be 4. So, F = 8. So, the seven-digit number is 7412589.
Page 5
1
UPSC 2022 - CSAT SOLUTION
Directions for the following 3 (three) items:
Read the following two passages and answer the items that follow the passages. Your answers to these
items should be based on the passages only.
Passage –1
The main threat to maintaining progress in human development comes from the increasingly evident
unsustainability of production and consumption patterns. Current production models rely heavily on
fossil fuels. We now know that this is unsustainable because the resources are finite. The close link
between economic growth and greenhouse gas emissions needs to be served for human development to
become truly sustainable. Some developed countries have begun to alleviate the worst effects by
expanding recycling and investing in public transport and infrastructure. But most developing countries
are hampered by the high costs and low availability of clean energy sources. Developed countries need
to support developing countries' transition to sustainable human development.
Q.1. Unsustainability in production pattern is due to which of the following?
1. Heavy dependence on fossil fuels
2. Limited availability of resources
3. Expansion of recycling
Select the correct answer using the code given below.
(a) 1 and 2 only
(b) 2 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer: (a)
Statement 1 is correct: The passage directly mentions, “the increasingly evident unsustainability of
production and consumption patterns. Current production models rely heavily on fossil fuels.”.
Therefore, heavy dependence on fossil fuels is a reason, as per the author, for the unsustainability of
production patterns.
Statement 2 is correct: Again, the author directly states, “the increasingly evident unsustainability of
production and consumption patterns. Current production models rely heavily on fossil fuels. We now
know that this is unsustainable because the resources are finite. “. Therefore, this statement is correct
as well.
Statement 3 is incorrect: The passage states that “Some developed countries have begun to alleviate
the worst effects by expanding recycling”. This means that some countries are trying to reduce the
effects of unsustainable production via recycling and other methods. Therefore, recycling would reduce
the unsustainability in production patterns rather than aggravate it.
2
Q.2. Consider the following statements:
Developed countries can support developing countries' transition to sustainable human
development by
1. making clean energy sources available at low cost
2. providing loans for improving their public transport at nominal interest rates
3. encouraging them to change their production and consumption patterns
Which of the statements given above is/are correct?
(a) 1 only
(b) 1 and 2 only
(c) 2 and 3 only
(d) 1, 2 and 3
Answer: (a/d)
Statement 1 is correct: The author mentions high costs and low availability of clean energy sources.
Immediately after that, he states that “Developed countries need to support developing countries'
transition to sustainable human development”. Therefore, the first statement is correct and it directly
follows the assertion made.
Explanation for Statement 2: Whether this statement is correct or incorrect depends upon whether we
opt for a narrow or broader interpretation of the passage. The passage mentions, “But most developing
countries are hampered by the high costs and low availability of clean energy sources.” Therefore, it
seems that the author is only focussing on issues related to high costs and low availability of clean
energy sources as hindrances for developed countries in transitioning towards sustainable human
development.
However, (taking a broader view) the question does mention “can”- and providing loans for improving
their public transport at nominal interest rates is certainly one way where developed countries can help
developing countries especially to alleviate the worst effects of unsustainable development.
Explanation for Statement 3: Likewise, this statement would be incorrect if we take a narrow
interpretation of the passage, as it specifically mentions high costs and low availability of clean energy
sources as hindrances for developed countries in transitioning towards sustainable human development.
But again, the question states “can” and encouragement (via finance etc.) to change production and
consumption patterns is certainly an area where developed countries could support the developing ones.
3
Passage –2
Unless the forces and tendencies which are responsible for destroying the country's environment are
checked in the near future and afforestation of denuded areas is taken up on a massive scale, the
harshness of the climatic conditions and soil erosion by wind and water will increase to such an extent
that agriculture, which is the mainstay of our people, will gradually become impossible. The desert
countries of the world and our own desert areas in Rajasthan are a grim reminder of the consequences
of large-scale deforestation. Pockets of desert-like landscape are now appearing in other parts of the
country including the Sutlej-Ganga Plains and Deccan Plateau. Where only a few decades back there
used to be lush green forests with perennial streams and springs, there is only brown earth, bare of
vegetation, without any water in the streams and springs except in the rainy season.
Q.3. According to the passage given above, deforestation and denudation will ultimately lead to
which of the following?
1. Depletion of soil resource
2. Shortage of land for the common man
3. Lack of water for cultivation
Select the correct answer using the code given below.
(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer: (c)
Statement 1 is correct: The passage mentions, “The desert countries of the world and our own desert
areas in Rajasthan are a grim reminder of the consequences of large-scale deforestation. Pockets of
desert-like landscape are now appearing in other parts of the country including the Sutlej-Ganga Plains
and Deccan Plateau. Where only a few decades back there used to be lush green forests with perennial
streams and springs, there is only brown earth, bare of vegetation, without any water in the streams and
springs except in the rainy season.”. This supports the assertion of the author that deforestation and
denudation will ultimately lead to the depletion of soil resources.
Statement 2 is incorrect: This statement goes beyond the scope of the passage. The passage nowhere
mentions anything related to the common man.
Statement 3 is correct: This is supported by the part in the passage which mentions, “the harshness of
the climatic conditions” and “Where only a few decades back there used to be lush green forests with
perennial streams and springs, there is only brown earth, bare of vegetation, without any water in the
streams and springs except in the rainy season”.
Q.4. What is the value of X in the sequence 20, 10, 10, 15, 30, 75, X?
(a) 105
(b) 120
(c) 150
(d) 225
Answer: (d)
The given series is:
20, 10, 10, 15, 30, 75, X?
The terms are decreasing in the initial half, and then they start increasing. The speed at which they
increase at the latter half suggest that multiplication may be involved.
The pattern is as follows:
20 × 0.5 = 10
10 × 1 = 10
4
10 × 1.5 = 15
15 × 2 = 30
30 × 2.5 = 75
75 × 3 = 225
Q.5. An Identity Card has the number ABCDEFG, not necessarily in that order, where each letter
represents a distinct digit (1, 2, 4, 5, 7, 8, 9 only). The number is divisible by 9. After deleting
the first digit from the right, the resulting number is divisible by 6. After deleting two digits
from the right of original number, the resulting number is divisible by 5. After deleting three
digits from the right of original number, the resulting number is divisible by 4. After deleting
four digits from the right of original number, the resulting number is divisible by 3. After
deleting five digits from the right of original number, the resulting number is divisible by 2.
Which of the following is a possible value for the sum of the middle three digits of the number?
(a) 8
(b) 9
(c) 11
(d) 12
Answer: (a)
The number has 7 digits, and has been denoted by: ABCDEFG
These letters can be replaced by 1, 2, 4, 5, 7, 8, 9, not necessarily in the same order.
We have to find the possible value of C + D + E
The original number (ABCDEFG) is divisible by 9. It has to be as 1 + 2 + 4 + 5 + 7 + 8 + 9 = 36, which
is divisible by 9. This information is utterly useless.
After deleting 1 digit from the right, the resulting number (ABCDEF) is divisible by 6. It means that, F
= 2, 4 or 8 (i.e. an even number).
Also, if even after removing G, the remaining number is divisible by 3, then it means G = 9.
After deleting 3 digits from the right, the resulting number (ABCD) is divisible by 4. It means that, D
= 2, 4 or 8 (i.e. an even number).
After deleting 5 digits from the right, the resulting number (AB) is divisible by 2. It means that, B = 2,
4 or 8 (i.e. an even number).
So, F, D and B are even numbers (2, 4 or 8). And, A, C, E, and G are odd numbers (1, 5, 7 or 9).
After deleting 2 digits from the right, the resulting number (ABCDE) is divisible by 5. It means that, E
= 5.
So, we just have to find C + D + E = C + D + 5, which must be an even number as C is odd (1, or 7),
and D is even (2, 4, or 8).
On observing the options, we can see that C must be 1 and D must be 2. So, C + D + E = 1 + 2 + 5 = 8.
Note: This information was also redundant - After deleting 4 digits from the right, the resulting number
(ABC) is divisible by 3. But it may be useful if we want to know the entire number. The only odd
number remaining is 7. So, A = 7. So, the ABC is actually 7B1. B can be 4 or 8. But for 7B1 to be
divisible by 3, B must be 4. So, F = 8. So, the seven-digit number is 7412589.
5
Q.6. Two friends X and Y start running and they run together for 50 m in the same direction and
reach a point. X turns right and runs 60 m, while Y turns left and runs 40m. Then X turns left
and runs 50m and stops, while Y turns right and runs 50 m and then stops. How far are the two
friends from each other now?
(a) 100 m
(b) 90 m
(c) 60 m
(d) 50 m
Answer: (a)
The path taken by them has been represented below:
It’s pretty clear that they are 40 + 60 = 100 m apart at the end of their run.
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