Question Detail

Ages of two persons differ by 16 years. If 6 year ago, the elder one be 3 times as old the younger one, find their present age

12,28
14,30
16,32
18,34

Answer: Option B

Explanation:

Let the age of younger person is x,
Then elder person age is (x+16)
=> 3(x-6) = (x+16-6) [6 years before]
=> 3x-18 = x+10
=> x = 14.
So other person age is x + 16 = 30

1. The ratio between the present ages of P and Q is 6:7. If Q is 4 years old than P, what will be the ratio of the ages of P and Q after 4 years

Answer: Option A

Explanation:

Let P age and Q age is 6x years and 7x years.
Then 7x - 6x = 4 <=> x = 4

So required ratio will be (6x+4): (7x+4) => 28:32 => 7:8

2. Ten years ago A was half of B in age. If the ratio of their present ages is 3 : 4, what will be the total of their present ages

Answer: Option B

Explanation:

Let A's age 10 years ago = x years.
Then, B's age 10 years ago = 2x years.
(x + 10) / (2x+ lO) = 3/4
=> x = 5.
So, the total of their present ages =(x + 10 + 2x + 10)
= (3x + 20) = 35 years.

3. A person's present age is two-fifth of the age of his mother. After 8 years, he will be one-half of the age of his mother. How old is the mother at present

Answer: Option B

Explanation:

Let the mother's present age be x years.
Then, the person's present age = (2/5 x) years.

=> (2/5 x + 8/2) = 1 (x + 8)
=> 2(2x + 40) = 5(x + 8)
=> x = 40

4. The total age of A and B is 12 years more than the total age of B and C. C is how many year younger than A

Answer: Option B

Explanation:

Given that A+B = 12 + B + C
=> A – C = 12 + B – B = 12
=> C is younger than A by 12 years

5. The ages of two persons differ by 16 years. 6 years ago, the elder one was 3 times as old as the younger one. What are their present ages of the elder person

Answer: Option D

Explanation:

Let's take the present age of the elder person = x
and the present age of the younger person = x – 16
(x – 6) = 3 (x-16-6)
=> x – 6 = 3x – 66
=> 2x = 60
=> x = 60/2 = 30