Question Detail

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

1. Tanya's grandfather was 8 times older to her 16 years ago. He would be 3 times of her age 8 years from now. What was ratio of ages of Tanya and her grandfather 8 years ago.

11:50
11:51
11:53
11:54

Answer: Option C

Explanation:

Let, Tanya age 16 years ago = x,
Grandfather's age 16 years ago = 8x.

8 years from now, 3(x+16+8) = (8x+16+8)
=> x = 48/5

8 years ago ratio was:

\begin{aligned}
=> \frac{x+8}{8x+8} = \frac{\frac{48}{5}+8}{8 \times \frac{48}{5}+8}
\end{aligned}

\begin{aligned}
=> \frac{88}{424} = \frac{11}{53}
\end{aligned}

2. Raju age after 15 years will be 5 times his age 5 years back, What is the present age of Raju

Answer: Option C

Explanation:

Clearly,
x+15 = 5(x-5)
<=> 4x = 40 => x = 10

3. Sushil was thrice as old as Snehal 6 years back. Sushil will be times as old as Snehal 6 years hence. How old is Snehal today

Answer: Option A

Explanation:

Let Snehals age 6 years back = x.
Then, Sushils age 6 years back = 3x.
(5/3) * (X + 6 + 6) = (3X + 6 + 6)
So 5(x+ 12) = 3(3x+ 12),
so x=6.
Snehal Age = (x+ 6) years = 12 years

4. Total of the ages of A, B ahd C at present is 90 years. Ten years ago, the ratio of their ages was 1: 2: 3. What is the age of B at present

Answer: Option B

Explanation:

Let their ages 10 years ago is x, 2x and 3x years.
10 + 2x + 10 + 3x + 10 = 90 hence x= 10
B’s present age = (2x + 10) =30 years

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 his son is

20 years
21 years
22 years
24 years

Answer: Option C

Explanation:

Let the son's present age be x years. Then, man's present age = (x + 24) years
=> (x + 24) + 2 = 2(x + 2)
=> x + 26 = 2x + 4
So, x = 22