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. 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. 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

3. 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

4. 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

5. Ratio between Rahul and Deepak is 4:3, After 6 Years Rahul age will be 26 years. What is Deepak present age.

Answer: Option B

Explanation:

Present age is 4x and 3x,
=> 4x + 6 = 26 => x = 5

So Deepak age is = 3(5) = 15