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Ex.1 If a, a 2, a 4 are consecutive prime numbers. Then how many solutions ‘a’ can have? (1) one (2) two (3) three (4) more than three Sol. No even value of ‘a’ satisfies this. So ‘a’ should be odd. But out of three consecutive odd numbers, atleast one number is a multiple of 3. So, only possibility is a = 3 and the numbers are 3, 5, 7. Answer: (1) This is given is your binder but I think the ques is incomplete. Either u should mention that all prime numbers a divisible by three?
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Ex.1 If a, a 2, a 4 are consecutive prime numbers. Then how many s...
Question Analysis:
The question asks about the possible values of 'a' if 'a', 'a+2', and 'a+4' are consecutive prime numbers. We need to determine the number of solutions for 'a'.

Given Information:
- 'a', 'a+2', and 'a+4' are consecutive prime numbers.

Solution:
To find the possible values of 'a', we need to consider the properties of prime numbers.

Property 1: All prime numbers except 2 are odd.
Property 2: Among any three consecutive odd numbers, at least one number is a multiple of 3.

Analysis of Properties:
From Property 1, we can conclude that 'a' must be an odd number. If 'a' were even, it would not be a prime number.

From Property 2, we know that among any three consecutive odd numbers, at least one number is a multiple of 3. Therefore, if 'a' is the first number in the sequence, then 'a+2' or 'a+4' must be divisible by 3. However, since 'a+2' and 'a+4' are prime numbers, they cannot be divisible by 3. Therefore, 'a' cannot be the first number in the sequence.

Hence, the only possibility is that 'a' is equal to 3. In this case, the three consecutive prime numbers are 3, 5, and 7.

Conclusion:
Based on the given information and the properties of prime numbers, the only solution for 'a' is 3. Therefore, the number of solutions for 'a' is one.

Answer: (1) one
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Directions : Ten pilgrims A, B, C, D, E, F, G, H, I and J visited Haridwar on either 10th or 24th of January, February, March, April and May not necessarily in the same order. They took a train journey to Haridwar from their hometown. Each took a different time in hours (integral valu e) to reach the destination. Pilgrims taking a consecutive number of hours did not travel on consecutive turns. A person taking an odd number of hours travelled in a month with an odd number of days and a person taking an even number of hours travelled in a month with an even number of days. Consider the year to be 2017. A took 33 hours to reach his destination A and H had their journeys at a gap of 2 persons Number of persons who travelled after J was one more than the number of persons who travelled before H. J travelled after H F and E travelled at a gap of 1 person and F took 7 hours more than that taken by E to reach the destination A and F took consecutive number of hours. J and C travelled in consecutive months but not on consecutive turns C took 8 hours less than that taken by D who travelled on March 24 Journey taken on February 10 was of 32 hours B took 36 hours to complete his journey B and I travelled at a gap of 2 persons G took 19 hours to reach his destination I travelled at a gap of 1 person from the one who took a journey of 29 hours H took 2 hours less than that taken by D who took less than 30 hours to complete his journey The person travelling on 24th February took 24 hours to complete his journey C and J took consecutive number of hours.How many people have had travel time less than that of I's travel time?

Directions: Ten pilgrims A, B, C, D, E, F, G, H, I and J visited Haridwar on either 10th or 24th of months of January, February, March, April and May not necessarily in the same order. They took a train journey to Haridwar from their hometown. Each took a different time in hours (integral valu e) to reach the destination. Pilgrims taking consecutive number of hours did not travel on consecutive turns. A person taking odd number of hours travelled in a month with odd number of days and a person taking even number of hours travelled in a month with even number of days. Consider the year to be 2017. A took 33 hours to reach his destination A and H had their journeys at a gap of 2 persons Number of persons who travelled after J was one more than the number of persons who travelled before H. J travelled after H F and E travelled at a gap of 1 person and F took 7 hours more than that taken by E to reach the destination A and F took consecutive number of hours. J and C travelled in consecutive months but not on consecutive turns C took 8 hours less than that taken by D who travelled on March 24 Journey taken on February 10 was of 32 hours B took 36 hours to complete his journey B and I travelled at a gap of 2 persons G took 19 hours to reach his destination I travelled at a gap of 1 person from the one who took a journey of 29 hours H took 2 hours less than that taken by D who took less than 30 hours to complete his journey The person travelling on 24th February took 24 hours to complete his journey C and J took consecutive number of hours. Q. How many persons have had travel time less than that of I's travel time?

Directions : Ten pilgrims A, B, C, D, E, F, G, H, I and J visited Haridwar on either 10th or 24th of months of January, February, March, April and May not necessarily in the same order. They took a train journey to Haridwar from their hometown. Each took a different time in hours (integral valu e) to reach the destination. Pilgrims taking a consecutive number of hours did not travel on consecutive turns. A person taking an odd number of hours travelled in a month with an odd number of days and a person taking an even number of hours travelled in a month with an even number of days. Consider the year to be 2017. A took 33 hours to reach his destination A and H had their journeys at a gap of 2 persons Number of persons who travelled after J was one more than the number of persons who travelled before H. J travelled after H F and E travelled at a gap of 1 person and F took 7 hours more than that taken by E to reach the destination A and F took consecutive number of hours. J and C travelled in consecutive months but not on consecutive turns C took 8 hours less than that taken by D who travelled on March 24 Journey taken on February 10 was of 32 hours B took 36 hours to complete his journey B and I travelled at a gap of 2 persons G took 19 hours to reach his destination I travelled at a gap of 1 person from the one who took a journey of 29 hours H took 2 hours less than that taken by D who took less than 30 hours to complete his journey The person travelling on 24th February took 24 hours to complete his journey C and J took consecutive number of hours.What was the difference between the travel time of H and E?

Directions: Ten pilgrims A, B, C, D, E, F, G, H, I and J visited Haridwar on either 10th or 24th of months of January, February, March, April and May not necessarily in the same order. They took a train journey to Haridwar from their hometown. Each took a different time in hours (integral valu e) to reach the destination. Pilgrims taking consecutive number of hours did not travel on consecutive turns. A person taking odd number of hours travelled in a month with odd number of days and a person taking even number of hours travelled in a month with even number of days. Consider the year to be 2017. A took 33 hours to reach his destination A and H had their journeys at a gap of 2 persons Number of persons who travelled after J was one more than the number of persons who travelled before H. J travelled after H F and E travelled at a gap of 1 person and F took 7 hours more than that taken by E to reach the destination A and F took consecutive number of hours. J and C travelled in consecutive months but not on consecutive turns C took 8 hours less than that taken by D who travelled on March 24 Journey taken on February 10 was of 32 hours B took 36 hours to complete his journey B and I travelled at a gap of 2 persons G took 19 hours to reach his destination I travelled at a gap of 1 person from the one who took a journey of 29 hours H took 2 hours less than that taken by D who took less than 30 hours to complete his journey The person travelling on 24th February took 24 hours to complete his journey C and J took consecutive number of hours. Q. What was the difference between the travel time of H and E?

Directions : Ten pilgrims A, B, C, D, E, F, G, H, I and J visited Haridwar on either 10th or 24th of January, February, March, April and May not necessarily in the same order. They took a train journey to Haridwar from their hometown. Each took a different time in hours (integral valu e) to reach the destination. Pilgrims taking a consecutive number of hours did not travel on consecutive turns. A person taking an odd number of hours travelled in a month with an odd number of days and a person taking an even number of hours travelled in a month with an even number of days. Consider the year to be 2017. A took 33 hours to reach his destination A and H had their journeys at a gap of 2 persons Number of persons who travelled after J was one more than the number of persons who travelled before H. J travelled after H F and E travelled at a gap of 1 person and F took 7 hours more than that taken by E to reach the destination A and F took consecutive number of hours. J and C travelled in consecutive months but not on consecutive turns C took 8 hours less than that taken by D who travelled on March 24 Journey taken on February 10 was of 32 hours B took 36 hours to complete his journey B and I travelled at a gap of 2 persons G took 19 hours to reach his destination I travelled at a gap of 1 person from the one who took a journey of 29 hours H took 2 hours less than that taken by D who took less than 30 hours to complete his journey The person travelling on 24th February took 24 hours to complete his journey C and J took consecutive number of hours.How many hours did J take to complete his journey?

Ex.1 If a, a 2, a 4 are consecutive prime numbers. Then how many solutions ‘a’ can have? (1) one (2) two (3) three (4) more than three Sol. No even value of ‘a’ satisfies this. So ‘a’ should be odd. But out of three consecutive odd numbers, atleast one number is a multiple of 3. So, only possibility is a = 3 and the numbers are 3, 5, 7. Answer: (1) This is given is your binder but I think the ques is incomplete. Either u should mention that all prime numbers a divisible by three?
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Ex.1 If a, a 2, a 4 are consecutive prime numbers. Then how many solutions ‘a’ can have? (1) one (2) two (3) three (4) more than three Sol. No even value of ‘a’ satisfies this. So ‘a’ should be odd. But out of three consecutive odd numbers, atleast one number is a multiple of 3. So, only possibility is a = 3 and the numbers are 3, 5, 7. Answer: (1) This is given is your binder but I think the ques is incomplete. Either u should mention that all prime numbers a divisible by three? for CAT 2024 is part of CAT preparation. The Question and answers have been prepared according to the CAT exam syllabus. Information about Ex.1 If a, a 2, a 4 are consecutive prime numbers. Then how many solutions ‘a’ can have? (1) one (2) two (3) three (4) more than three Sol. No even value of ‘a’ satisfies this. So ‘a’ should be odd. But out of three consecutive odd numbers, atleast one number is a multiple of 3. So, only possibility is a = 3 and the numbers are 3, 5, 7. Answer: (1) This is given is your binder but I think the ques is incomplete. Either u should mention that all prime numbers a divisible by three? covers all topics & solutions for CAT 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Ex.1 If a, a 2, a 4 are consecutive prime numbers. Then how many solutions ‘a’ can have? (1) one (2) two (3) three (4) more than three Sol. No even value of ‘a’ satisfies this. So ‘a’ should be odd. But out of three consecutive odd numbers, atleast one number is a multiple of 3. So, only possibility is a = 3 and the numbers are 3, 5, 7. Answer: (1) This is given is your binder but I think the ques is incomplete. Either u should mention that all prime numbers a divisible by three?.
Solutions for Ex.1 If a, a 2, a 4 are consecutive prime numbers. Then how many solutions ‘a’ can have? (1) one (2) two (3) three (4) more than three Sol. No even value of ‘a’ satisfies this. So ‘a’ should be odd. But out of three consecutive odd numbers, atleast one number is a multiple of 3. So, only possibility is a = 3 and the numbers are 3, 5, 7. Answer: (1) This is given is your binder but I think the ques is incomplete. Either u should mention that all prime numbers a divisible by three? in English & in Hindi are available as part of our courses for CAT. Download more important topics, notes, lectures and mock test series for CAT Exam by signing up for free.
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