Age

Question 1

Sum of the age of 4 children born at interval of 4 years is 36. What is the age of youngest child?

• A. 2 years
• B. 3 years
• C. 4 years
• D. 5 years

Answer: (B)

Let the ages of children be x, (x+4), 
(x+8) and (x+12) years.

Then x + x + 4 + x + 8 + x +12 = 36
                       4x + 24 = 36
                             4x = 12
                              x = 3
Age of the youngest child = x = 3 years

Question 2

A is 5 years older than B who is thrice as old as C. If the total of ages of A, B and C is 40, then how old is C ?

• A. 6
• B. 7
• C. 5
• D. 8

Answer: (C)

Let C’s age be x years then B’s age be 3x
years and A’s age be (3x+5) years

Therefore  x + 3x + (3x + 5) = 40
                      7x + 5 = 40
                          7x = 35
                            x = 5

Question 3

Present age of Vinod and Ashok are in ratio of 3:4 respectively. After 5 years, the ratio of their ages becomes 7:9 respectively. What is Ashok’s present age is ?

• A. 40 years
• B. 28 years
• C. 32 years
• D. 36 years

Answer: (A)

Let the present age of Vinod and Ashok be 3x years and 4x years respectively.

Then (3x+5) / (4x+5)  = 7 / 9 

∴ 9(3x + 5) = 7(4x + 5)
∴ 27x + 45 = 28x + 35
∴ x = 10
∴ Ashok’s present age = 4x = 40 years 

Question 4

At present father’s age is thrice of son’s age. After 15 years father’s age will be double of son’s age. What is son’s present age?

• A. 16 years
• B. 15 years
• C. 12 years
• D. 10 years

Answer: (B)

Let the present age of son and father be x years and 3x years respectively.

Then (3x + 15) = 2(x + 15)

∴ 3x + 15 = 2x + 30
∴ x = 15
∴ Son’s present age = x = 15 years. 

Question 5

At present father’s age is thrice of son’s age. After 15 years father’s age will be double of son’s age. What is son’s present age?

• A. 16 years
• B. 15 years
• C. 12 years
• D. 10 years

Answer: (B)

Let the present age of son and father be x years and 3x years respectively.

Then (3x + 15) = 2(x + 15)

∴ 3x + 15 = 2x + 30
∴ x = 15
∴ Son’s present age = x = 15 years. 

Question 6

At present, the ratio between ages of Ram and Shyam is 6:5 respectively. After 7 years, Shyam’s age will be 32 years. What is the present age of Ram?

• A. 32
• B. 40
• C. 30
• D. 36

Answer: (C)

Let the present age of Ram and Shyam be 6x years and 5x years respectively.

Then 5x + 7 = 32
∴      5x = 25
∴        x = 5
∴ Present age of Ram = 6x = 30 years

Question 7

The present ages of A, B and C are in proportions 4:5:9. Nine years ago, sum of their ages was 45 years. Find their present ages in years

• A. 15,20,35
• B. 20,24,36
• C. 20,25,45
• D. 16,20,36

Answer: (D)

Let the current ages of A, B and C be ax years, 5x years and 9x respectively.

Then (4x-9) + (5x-9) + (9x-9) =45
∴ 18x – 27 = 45
∴ 18x = 72
∴ x = 4

Present ages of A, B and C are 4x = 16, 5x = 20, 9x = 36 respectively.

Question 8

A person’s present age is one third of the age of his mother. After 12 years, his age will be one half of the age of his mother. What is present age of his mother?

• A. 30
• B. 34
• C. 38
• D. 36

Answer: (D)

Le the present ages of son and his mother are x years and 3x years.

Then (3x + 12) = 2( x + 12)
∴ 3x + 12 = 2x + 24
∴ x = 12
∴ Present age of mother = 3x = 36 years 

Question 9

A is as older than B as he is younger than C.If the sum of ages of B and C is 68 years. What is the present age of A?

• A. 24 years
• B. 34 years
• C. 28 years
• D. 32 years

Answer: (B)

A – B = C – A
∴ 2A = B + C
And also given that B + C = 68
∴ 2A = 68
∴   A = 34 

Question 10

After 15 years, Paul’s age will be 5 times his age 5 years back. Find out his present age.

• A. 10 years
• B. 14 years
• C. 12 years
• D. 11 years

Answer: (A)

Let his present age be x years. Paul’s age after 15 years = (x+15) years. Paul’s age 5 years back = (x-5) years. Hence, x+15 = 5(x-5) ⇒ x+15 = 5x-25 ⇒ 4x = 40 ⇒ x = 10.