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. Ratio of ages of three persons is 4:7:9, Eight years ago, the sum of their ages was 56. Find their present ages.

16,35,36
12,28,36
16,28,27
16,28,36

Answer: Option D

Explanation:

Let the present ages are 4x, 7x, 9x.
=> (4x-8) + (7x-8) + (9x-8) = 56
=> 20x = 80
=> x = 4

So their present ages are: 16,28,36

2. Six years ago, the ratio of the ages of Kunal and Sagar was 6:5, Four years hence, the ratio of their ages will be 11:10. What is Sagar age at present

10 years
12 years
14 years
16 years

Answer: Option D

Explanation:

Let six years ago the age of Kunal and Sagar are 6x and 5x resp.
then,
\begin{aligned}
=> \frac{(6x+6)+4}{(5x+6)+4} = \frac{11}{10}
\end{aligned}
\begin{aligned}
<=> 10(6x+10) = 11(5x+10)
\end{aligned}
\begin{aligned}
<=> 5x = 10 => x = 2
\end{aligned}

So Sagar age is (5x+6) = 16

3. The sum of the present ages of a father and his son is 60 years. Six years ago, father's age was five times the age of the son. After 6 years, son's age will be

15 years
18 years
20 years
22 years

Answer: Option C

Explanation:

Clue : (60 - x) - 6 = 5(x - 6)

4. 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

5. A man is 24 years older than his son. In two years, his age will be twice the age of his son. The present age of this son is

21 years
22 years
23 years
24 years

Answer: Option B

Explanation:

Let's Son age is x, then Father age is x+24.
=> 2(x+2) = (x+24+2)
=> 2x+4 = x+26
=> x = 22 years