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All questions of Simplification & Approximation for RRB Group D / RPF Constable Exam
7.8 + 5.4 x 8.2 = ?- a)52.08
- b)108.24
- c)48.05
- d)102.05
- e)None of these
Correct answer is option 'A'. Can you explain this answer?
7.8 + 5.4 x 8.2 = ?
a)
52.08
b)
108.24
c)
48.05
d)
102.05
e)
None of these
|
Knowledge Center answered |
Solution for 7.8 + 5.4 × 8.2
We solve using the order of operations (BODMAS):
- First, perform the multiplication:
5.4 × 8.2 = 44.28 - Next, add the result to 7.8:
7.8 + 44.28 = 52.08
Correct Answer: A: 52.08
- a)2 - √3
- b)2 + √3
- c)16 - √3
- d)14 - √3
- e)None of these
Correct answer is option 'C'. Can you explain this answer?
a)
2 - √3
b)
2 + √3
c)
16 - √3
d)
14 - √3
e)
None of these
|
|
Knowledge Center answered |
Given expression:
[(2 + √3) / (2 - √3)] + [(2 - √3) / (2 + √3)] + [(√3 - 1) / (√3 + 1)]
- Simplify the first two terms:
- The denominator simplifies to 1.
- The numerator becomes 14.
- Result: 14.
- Simplify the third term:
- Rationalize the denominator to get 2 - √3.
- Add the results:
- 14 + (2 - √3) = 14 - √3.
Correct Answer: C: 14 - √3
(?)3 x (55) ÷ 225 = 3000- a)6
- b)8
- c)5
- d)9
- e)None of these
Correct answer is option 'A'. Can you explain this answer?
(?)3 x (55) ÷ 225 = 3000
a)
6
b)
8
c)
5
d)
9
e)
None of these
|
|
Knowledge Center answered |
To solve (?)³ × (5⁵) ÷ 225 = 3000, follow these steps:
- Rearrange the equation:
(?)³ = (3000 × 225) ÷ 5⁵ - Calculate 5⁵:
5⁵ = 3125 - Simplify the numerator:
3000 × 225 = 675000 - Divide:
675000 ÷ 3125 = 216 - Find the cube root of 216:
√³(216) = 6
Correct Answer: A: 6
- a)62/3
- b)6
- c)31/3
- d)3
- e)None of these
Correct answer is option 'D'. Can you explain this answer?
a)
62/3
b)
6
c)
31/3
d)
3
e)
None of these
|
Faizan Khan answered |
On solving, we will get x = 3 or x = -2
Ignoring the negative value answer is 3.
Ignoring the negative value answer is 3.
- a)51
- b)59
- c)57
- d)53
- e)None of these
Correct answer is option 'C'. Can you explain this answer?
a)
51
b)
59
c)
57
d)
53
e)
None of these
|
|
Knowledge Center answered |
Solution for ∛185193
To solve ∛185193, we find the cube root:
- The cube root of 185193 is 57, since 57³ = 185193.
Correct Answer: C: 57
If the sum of a number and its square is 156, what is the number?- a)16
- b)14
- c)12
- d)13
- e)None
Correct answer is option 'C'. Can you explain this answer?
If the sum of a number and its square is 156, what is the number?
a)
16
b)
14
c)
12
d)
13
e)
None
|
|
Knowledge Center answered |
Let the number be x.
x+x2=156
x2+x−156=0
(x−12)(x+13)=0
x+x2=156
x2+x−156=0
(x−12)(x+13)=0
x+13=0
x=−13 (Since x is a natural number)
x−12=0
x=12
x=−13 (Since x is a natural number)
x−12=0
x=12
5616 ÷ 18 ÷ 8 = ?- a)34
- b)39
- c)38
- d)37
- e)None of these
Correct answer is option 'B'. Can you explain this answer?
5616 ÷ 18 ÷ 8 = ?
a)
34
b)
39
c)
38
d)
37
e)
None of these
|
Kavya Saxena answered |
5616 ÷ 18 = 312
312 / 8 = 39
312 / 8 = 39
12.5 * 14 ÷ 8.75 + 12 = 20 + ? - a)14
- b)11
- c)12
- d)18
- e)15
Correct answer is option 'C'. Can you explain this answer?
12.5 * 14 ÷ 8.75 + 12 = 20 + ?
a)
14
b)
11
c)
12
d)
18
e)
15
|
Sankar Rane answered |
12.5 * 1.6 = 20 ; 20 + 12 – 20 = 12
47.932 + 56 + 97.168 – 67 – 78.3 – 22.7- a)33
- b)32.1
- c)33.1
- d)34.1
- e)None
Correct answer is option 'C'. Can you explain this answer?
47.932 + 56 + 97.168 – 67 – 78.3 – 22.7
a)
33
b)
32.1
c)
33.1
d)
34.1
e)
None
|
|
Knowledge Center answered |
Expression:
( 47.932 + 56 + 97.168 - 67 - 78.3 - 22.7 )
Step 1: Add the positive terms:
( 47.932 + 56 + 97.168 = 201.1 )
Step 2: Add the negative terms:
( 67 + 78.3 + 22.7 = 168 )
Step 3: Subtract the sum of negative terms from the sum of positive terms:
( 201.1 - 168 = 33.1 )
Final Answer: The result of the expression is 33.1.
5610 ÷ 35.0625 * 25 = ?- a) 3000
- b) 2000
- c)5000
- d) 4000
- e) 6000
Correct answer is option 'D'. Can you explain this answer?
5610 ÷ 35.0625 * 25 = ?
a)
3000
b)
2000
c)
5000
d)
4000
e)
6000
|
Yash Patel answered |
5610 ÷ 35.0625 = 160; 160 * 25 = 4000
- a)2 - √2
- b)√2 - 2
- c)2
- d)-2
- e)None of these
Correct answer is option 'B'. Can you explain this answer?
a)
2 - √2
b)
√2 - 2
c)
2
d)
-2
e)
None of these
|
|
Prakhya Shrivastava answered |
√8 - √4 - √2
= 2√2 - 2 - √2
= √2-2
Hence option (b) is correct
= 2√2 - 2 - √2
= √2-2
Hence option (b) is correct
(85410 + 36885 + 24705) ÷ 1600 = ?- a)92.875
- b)91.875
- c)93.675
- d)92.675
- e)None of these
Correct answer is option 'B'. Can you explain this answer?
(85410 + 36885 + 24705) ÷ 1600 = ?
a)
92.875
b)
91.875
c)
93.675
d)
92.675
e)
None of these
|
Aisha Gupta answered |
(85410 + 36885 + 24705) = 147000; 147000/1600 = 91.875
? * (523.5 + 687.5) = 24220- a)24
- b)20
- c)28
- d) 27
- e)None of these
Correct answer is option 'B'. Can you explain this answer?
? * (523.5 + 687.5) = 24220
a)
24
b)
20
c)
28
d)
27
e)
None of these
|
|
Anaya Patel answered |
x * 1211 = 24220; x = 20
456 ÷ 24 * 38 – 958 + 364 = ?- a)167
- b) 146
- c)136
- d)128
- e)None of these
Correct answer is option 'D'. Can you explain this answer?
456 ÷ 24 * 38 – 958 + 364 = ?
a)
167
b)
146
c)
136
d)
128
e)
None of these
|
|
Faizan Khan answered |
456 ÷ 24 = 19; 19 * 38 = 722; 722 + 364 – 958 = 128
? % of 1400 – 18% of 750 = 159- a)27
- b)29
- c)17
- d)21
- e)None of these
Correct answer is option 'D'. Can you explain this answer?
? % of 1400 – 18% of 750 = 159
a)
27
b)
29
c)
17
d)
21
e)
None of these
|
All Film Mistakes answered |
21% of 1400 is 294 18 % of 750 is 135 294-135 is 159
(656 ÷ 164)² = √?- a)4
- b)16
- c)256
- d)400
- e)None of these
Correct answer is option 'C'. Can you explain this answer?
(656 ÷ 164)² = √?
a)
4
b)
16
c)
256
d)
400
e)
None of these
|
|
Alok Verma answered |
656 ÷ 164 = 4; √? = 16 ; ? = 256
(169 – 144)½ ÷ (64 + 36)½ = ?
- a)0.5
- b)0.25
- c)2.5
- d)5
- e)None of these
Correct answer is option 'A'. Can you explain this answer?
(169 – 144)½ ÷ (64 + 36)½ = ?
a)
0.5
b)
0.25
c)
2.5
d)
5
e)
None of these
|
|
Knowledge Center answered |
To solve the given expression:
1. Calculate the values inside the parentheses first: √(169 - 144 = 25) and √(64 + 36 = 100).
2. Now simplify the expression further: √25/√100 .
3. Calculate the square roots: 5/10
4. Finally, divide the two results: 0.5
Therefore, the correct answer is A: 0.5.
1. Calculate the values inside the parentheses first: √(169 - 144 = 25) and √(64 + 36 = 100).
2. Now simplify the expression further: √25/√100 .
3. Calculate the square roots: 5/10
4. Finally, divide the two results: 0.5
Therefore, the correct answer is A: 0.5.
- a)62
- b)58
- c)68
- d)66
- e)None of these
Correct answer is option 'E'. Can you explain this answer?
a)
62
b)
58
c)
68
d)
66
e)
None of these
|
|
Knowledge Center answered |
Solution for ( ? )² / 4 + √1521 = 1063
To solve ( ? )² / 4 + √1521 = 1063, follow these steps:
- Calculate the square root of 1521:
√1521 = 39 - Substitute into the equation and simplify:
( ? )² / 4 + 39 = 1063
( ? )² / 4 = 1063 - 39 = 1024 - Multiply by 4:
( ? )² = 1024 × 4 = 4096 - Take the square root:
? = √4096 = 64
Correct Answer: E: None of these
–224 + (–314) x (–9) = ?- a)2602
- b)547
- c)– 547
- d)–2602
- e)None of these
Correct answer is option 'A'. Can you explain this answer?
–224 + (–314) x (–9) = ?
a)
2602
b)
547
c)
– 547
d)
–2602
e)
None of these
|
|
Anaya Patel answered |
Option (a) 2602 is correct.
Explanation:-
{ Given,
-224 + ( - 314) * (-9)
According to BODMASS ;
=> -224 -314 * -9
=> -224 + 2826
=> 2602
=> 2602
12.5% of 350 * 8.4% of 250 = ?- a)912.75
- b)915.75
- c)913.75
- d)918.75
- e)916.75
Correct answer is option 'D'. Can you explain this answer?
12.5% of 350 * 8.4% of 250 = ?
a)
912.75
b)
915.75
c)
913.75
d)
918.75
e)
916.75
|
|
Aarav Sharma answered |
Given: 12.5% of 350 * 8.4% of 250
Calculation:
Step 1: Find 12.5% of 350
= (12.5/100) * 350
= 43.75
Step 2: Find 8.4% of 250
= (8.4/100) * 250
= 21
Step 3: Multiply the results of step 1 and step 2
= 43.75 * 21
= 918.75
Therefore, the answer is option D) 918.75.
Calculation:
Step 1: Find 12.5% of 350
= (12.5/100) * 350
= 43.75
Step 2: Find 8.4% of 250
= (8.4/100) * 250
= 21
Step 3: Multiply the results of step 1 and step 2
= 43.75 * 21
= 918.75
Therefore, the answer is option D) 918.75.
- a)6241
- b)6889
- c)6561
- d)5929
- e)None of thes
Correct answer is option 'C'. Can you explain this answer?
a)
6241
b)
6889
c)
6561
d)
5929
e)
None of thes
|
|
Anaya Patel answered |
C is the correct option. Solution-
4028÷53=76
6156÷76=81
So the value needed is a square of 81 which is 6561.
4028÷53=76
6156÷76=81
So the value needed is a square of 81 which is 6561.
Which one of the following fractions is the greatest?- a)1/7
- b)2/9
- c)4/11
- d)3/10
- e)None
Correct answer is option 'C'. Can you explain this answer?
Which one of the following fractions is the greatest?
a)
1/7
b)
2/9
c)
4/11
d)
3/10
e)
None
|
|
Knowledge Center answered |
1/7 = 0.1429
2/9 = 0.2222
4/11 = 0.3636
3/10 = 0.3
So, the greatest fraction is 4/11
2/9 = 0.2222
4/11 = 0.3636
3/10 = 0.3
So, the greatest fraction is 4/11
5.8 * 2.5 + 0.6 * 6.75 + 139.25 = ?- a)139.80
- b) 157.80
- c) 156.70
- d)170.70
- e)176.60
Correct answer is option 'B'. Can you explain this answer?
5.8 * 2.5 + 0.6 * 6.75 + 139.25 = ?
a)
139.80
b)
157.80
c)
156.70
d)
170.70
e)
176.60
|
|
Kavya Saxena answered |
5.8 * 2.5 + 0.6 * 6.75 + 139.25 = 157.80
- a)88
- b)74
- c)77
- d)84
- e)None of these
Correct answer is option 'D'. Can you explain this answer?
a)
88
b)
74
c)
77
d)
84
e)
None of these
|
|
Kavya Saxena answered |
8/21 * x = 1008
x = 21168 / 8
x = 2646
20*168÷14-40 = ? + 110- a)60
- b)30
- c)40
- d)80
- e)90
Correct answer is option 'E'. Can you explain this answer?
20*168÷14-40 = ? + 110
a)
60
b)
30
c)
40
d)
80
e)
90
|
Ravi Singh answered |
168/14 = 12; 20*12 – 240; 240 – 40 = 200; 200 – 110 = 90
(?)1/4/ 8 = 48/(?)3/4- a)324
- b)364
- c)384
- d)374
- e)314
Correct answer is option 'C'. Can you explain this answer?
(?)1/4/ 8 = 48/(?)3/4
a)
324
b)
364
c)
384
d)
374
e)
314
|
Devansh Tomar answered |
Let? =x
A/q
Croos multiple then
X=8×48
X= 384
A/q
Croos multiple then
X=8×48
X= 384
69.69 – 51.54 + 73.65 = ? + 32.42- a)26.38
- b)32.38
- c)43.38
- d)57.38
- e)59.38
Correct answer is option 'E'. Can you explain this answer?
69.69 – 51.54 + 73.65 = ? + 32.42
a)
26.38
b)
32.38
c)
43.38
d)
57.38
e)
59.38
|
|
Kavya Saxena answered |
69.69 – 51.54 = 18.15
18.15 + 73.65 = 91.80
91.80 – 32.42 = 59.38
18.15 + 73.65 = 91.80
91.80 – 32.42 = 59.38
- a)
- b)
- c)4
- d)
- e)None of these
Correct answer is 'C'. Can you explain this answer?
a)
b)
c)
4
d)
e)
None of these
|
|
Knowledge Center answered |
To solve 82/3, follow these steps:
- Interpret the fractional exponent:
82/3 = (∛8)2 - Find the cube root of 8:
∛8 = 2 - Square the result:
2² = 4
Correct Answer: C: 4
[(272-32)(124+176)]/(17*15-15) = ?- a)240
- b)320
- c)400
- d)380
- e)300
Correct answer is option 'E'. Can you explain this answer?
[(272-32)(124+176)]/(17*15-15) = ?
a)
240
b)
320
c)
400
d)
380
e)
300
|
|
Aarav Sharma answered |
Given expression: [(272-32)(124 176)]/(17*15-15)
Simplifying the expression step by step:
1. [(272-32)(124 176)] = 24000
2. (17*15-15) = 240
3. [(272-32)(124 176)]/(17*15-15) = 24000/240
4. [(272-32)(124 176)]/(17*15-15) = 100
Therefore, the correct answer is option 'E': 300.
Simplifying the expression step by step:
1. [(272-32)(124 176)] = 24000
2. (17*15-15) = 240
3. [(272-32)(124 176)]/(17*15-15) = 24000/240
4. [(272-32)(124 176)]/(17*15-15) = 100
Therefore, the correct answer is option 'E': 300.
8% of 800 x ? = 224- a)4.5
- b)3.5
- c)4
- d)3
- e)None of these
Correct answer is option 'B'. Can you explain this answer?
8% of 800 x ? = 224
a)
4.5
b)
3.5
c)
4
d)
3
e)
None of these
|
|
Divya answered |
8/100×800x=224 64x=224 x=3.5
- a)
- b)
- c)
- d)
- e)
Correct answer is option 'C'. Can you explain this answer?
a)
b)
c)
d)
e)
|
|
Knowledge Center answered |
= we know,
(4-3+13-8)+(1/2 - 1/7 + 2/7 -1/4)
= 6 + 11/28
= option C
(4-3+13-8)+(1/2 - 1/7 + 2/7 -1/4)
= 6 + 11/28
= option C
(764 x ?) ÷ 250 = 382
- a)135
- b)125
- c)115
- d)145
- e)None of these
Correct answer is option 'B'. Can you explain this answer?
(764 x ?) ÷ 250 = 382
a)
135
b)
125
c)
115
d)
145
e)
None of these
|
|
Knowledge Center answered |
Solution:
Given equation:
(764 x ?) ÷ 250 = 382
Solving for ?:
(764 x ?) = 382 x 250
? = (382 x 250) / 764
? = 125
Therefore, the value of ? is 125.
So, the correct answer is B: 125.
Given equation:
(764 x ?) ÷ 250 = 382
Solving for ?:
(764 x ?) = 382 x 250
? = (382 x 250) / 764
? = 125
Therefore, the value of ? is 125.
So, the correct answer is B: 125.
856 x 567 = ?- a)487064
- b)484218
- c)482784
- d)485352
- e)None of these
Correct answer is option 'D'. Can you explain this answer?
856 x 567 = ?
a)
487064
b)
484218
c)
482784
d)
485352
e)
None of these
|
Sajal Bdw answered |
An easy way (here) just multiply units digit of two number
6×7=42 so whatever the number will be it will have unit place 2 therefore the answer is D
6×7=42 so whatever the number will be it will have unit place 2 therefore the answer is D
(4270 ÷ 122) + ? = 200- a)165
- b)155
- c)175
- d)185
- e)None of these
Correct answer is option 'A'. Can you explain this answer?
(4270 ÷ 122) + ? = 200
a)
165
b)
155
c)
175
d)
185
e)
None of these
|
Nikita Singh answered |
4270 ÷ 122 = 35
200 – 35 = 165
200 – 35 = 165
What is the number in the unit place in (5427)641?- a)1
- b)7
- c)9
- d)3
- e)None
Correct answer is option 'B'. Can you explain this answer?
What is the number in the unit place in (5427)641?
a)
1
b)
7
c)
9
d)
3
e)
None
|
Deepali singhania answered |
The correct answer is B as the unit place will be 7 only .
8934 – 3257 + 481 = ? + 2578
- a)3250
- b)3580
- c)3560
- d)3480
- e)3520
Correct answer is option 'B'. Can you explain this answer?
8934 – 3257 + 481 = ? + 2578
a)
3250
b)
3580
c)
3560
d)
3480
e)
3520
|
Preeti Khanna answered |
Calculation:
- First, perform the subtraction: 8934 - 3257 = 5677
- Then, add 481 to the result: 5677 + 481 = 6158
- Finally, subtract 2578 from both sides to find the missing value: 6158 - 2578 = 3580
Therefore, the missing value is 3580. So, the answer is B: 3580.
- First, perform the subtraction: 8934 - 3257 = 5677
- Then, add 481 to the result: 5677 + 481 = 6158
- Finally, subtract 2578 from both sides to find the missing value: 6158 - 2578 = 3580
Therefore, the missing value is 3580. So, the answer is B: 3580.
16.23 * 12.9 + 17.32 = ?- a)224.87
- b)234.87
- c)244.87
- d)226.687
- e)None of these
Correct answer is option 'D'. Can you explain this answer?
16.23 * 12.9 + 17.32 = ?
a)
224.87
b)
234.87
c)
244.87
d)
226.687
e)
None of these
|
|
Aarav Sharma answered |
**Calculation:**
To find the product of 16.23, 12.9, and 17.32, we can multiply the first two numbers and then multiply the result by the third number.
1. Multiply 16.23 and 12.9:
16.23 * 12.9 = 209.547
2. Multiply the result from step 1 by 17.32:
209.547 * 17.32 = 3631.15324
**Final Answer:**
The product of 16.23, 12.9, and 17.32 is approximately 3631.15324.
Therefore, the correct answer is option D) 226.687.
To find the product of 16.23, 12.9, and 17.32, we can multiply the first two numbers and then multiply the result by the third number.
1. Multiply 16.23 and 12.9:
16.23 * 12.9 = 209.547
2. Multiply the result from step 1 by 17.32:
209.547 * 17.32 = 3631.15324
**Final Answer:**
The product of 16.23, 12.9, and 17.32 is approximately 3631.15324.
Therefore, the correct answer is option D) 226.687.
The sum of the digits of a two-digit number is 8. If the digits are reversed, the number is decreased by 54. Find the number.- a)42
- b)53
- c)17
- d)71
- e)None
Correct answer is option 'D'. Can you explain this answer?
The sum of the digits of a two-digit number is 8. If the digits are reversed, the number is decreased by 54. Find the number.
a)
42
b)
53
c)
17
d)
71
e)
None
|
|
Knowledge Center answered |
Let the two-digit number be represented as 10a + b, where:
- a is the tens digit.
- b is the one digit.
According to the problem:
- The sum of the digits is 8:a+b=8
- When the digits are reversed, the number is decreased by 54. The number with reversed digits is 10b + a. So:10a+b−(10b+a)=54Simplifying this equation:10a+b−10b−a=54
9a−9b=54
a−b=6
Now, we have two equations:
- a+b=8
- a−b=6
Add these two equations:
(a+b)+(a−b)=8+6
2a = 14
a=7
2a = 14
a=7
Substitute a=7 into a+b=8:
7+b=8 , b = 1
So, the number is 10a+b=10×7+1=71
Answer: The number is 71.
36 * 1.75 + 24 * 3.25 = ? - a)142
- b)141
- c)162
- d)182
- e)152
Correct answer is option 'B'. Can you explain this answer?
36 * 1.75 + 24 * 3.25 = ?
a)
142
b)
141
c)
162
d)
182
e)
152
|
|
Ravi Singh answered |
36 * 1.75 + 24 * 3.25 = 63 + 78 = 141
184 ÷ 46 ÷ 0.008 ÷ 12.5 = ?- a)30
- b)40
- c)60
- d)80
- e)None of these
Correct answer is option 'B'. Can you explain this answer?
184 ÷ 46 ÷ 0.008 ÷ 12.5 = ?
a)
30
b)
40
c)
60
d)
80
e)
None of these
|
|
Rhea Reddy answered |
184 ÷ 46 = 4; 4 ÷ 0.008 = 500; 500 ÷ 12.5 = 40
A number when divided by 1092 gives a remainder 60. What remainder would be obtained by dividing the same number by 28?- a)6
- b)2
- c)5
- d)4
- e)None
Correct answer is option 'D'. Can you explain this answer?
A number when divided by 1092 gives a remainder 60. What remainder would be obtained by dividing the same number by 28?
a)
6
b)
2
c)
5
d)
4
e)
None
|
Aspire Academy answered |
In these type of of questions we apply a trick by just dividing the given remainder by given no.
60 ÷ 28
remainder will come( 4)
60 ÷ 28
remainder will come( 4)
Find the number in the unit place in (321)321 x (325)326.- a)1
- b)5
- c)6
- d)8
- e)None
Correct answer is option 'B'. Can you explain this answer?
Find the number in the unit place in (321)321 x (325)326.
a)
1
b)
5
c)
6
d)
8
e)
None
|
|
Faizan Khan answered |
321 raised to 321=1 in unit digit and any number ending in 5 raised to any number has always 5 as unit digit, so 1×5=5
444 ÷ (16*1.5) = ?
- a)14.5
- b)16.5
- c)18.5
- d)20.5
- e)None of these
Correct answer is option 'C'. Can you explain this answer?
444 ÷ (16*1.5) = ?
a)
14.5
b)
16.5
c)
18.5
d)
20.5
e)
None of these
|
|
Rhea Reddy answered |
Given expression:
444 ÷ (16 × 1.5)
Step 1: Calculate the denominator
The denominator is: 16 × 1.5
16 × 1.5 = 24
Denominator = 24
Step 2: Divide the numerator by the denominator
Now divide: 444 ÷ 24 = 18.5
Final result = 18.5
The correct answer is: c) 18.5
444 ÷ (16 × 1.5)
Step 1: Calculate the denominator
The denominator is: 16 × 1.5
16 × 1.5 = 24
Denominator = 24
Step 2: Divide the numerator by the denominator
Now divide: 444 ÷ 24 = 18.5
Final result = 18.5
The correct answer is: c) 18.5
The sum of the digits of a two-digit number is 8. If the digits are reversed, the number is decreased by 54. Find the number.- a)42
- b)53
- c)17
- d)71
- e)None
Correct answer is option 'D'. Can you explain this answer?
The sum of the digits of a two-digit number is 8. If the digits are reversed, the number is decreased by 54. Find the number.
a)
42
b)
53
c)
17
d)
71
e)
None
|
Prerna Sen answered |
Let the units number be u; the tens be t.
A) t+u=8
B) 10u+t=10t+u+54
.
A) u=8-t
B)
10(8-t)+t=10t+8-t+54
80-10t+t=9t+62
80-9t=9t+62
18t=18
t=1
u=7
The number is 17.
- a)12
- b)15
- c)17
- d)16
- e)None
Correct answer is option 'D'. Can you explain this answer?
a)
12
b)
15
c)
17
d)
16
e)
None
|
Arjun Vinod answered |
√169 = 13
16 × 16 = 256 (ie, 16^2)
therefore
option d is the answer
16 × 16 = 256 (ie, 16^2)
therefore
option d is the answer
? / 529 = 324 / ? - a)325
- b)414
- c)456
- d)448
- e)352
Correct answer is option 'B'. Can you explain this answer?
? / 529 = 324 / ?
a)
325
b)
414
c)
456
d)
448
e)
352
|
|
Preeti Khanna answered |
x² = 529 * 324 ⇒ x = 23 * 18 = 414
Chapter doubts & questions for Simplification & Approximation - Mathematics for RRB Group D / RPF Constable 2025 is part of RRB Group D / RPF Constable exam preparation. The chapters have been prepared according to the RRB Group D / RPF Constable exam syllabus. The Chapter doubts & questions, notes, tests & MCQs are made for RRB Group D / RPF Constable 2025 Exam. Find important definitions, questions, notes, meanings, examples, exercises, MCQs and online tests here.
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Mathematics for RRB Group D / RPF Constable
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