Question Detail

Sachin is younger than Rahul by 7 years. If the ratio of their ages is 7:9, find the age of Sachin

23.5
24.5
12.5
14.5

Answer: Option B

Explanation:

If Rahul age is x, then Sachin age is x-7,
so (x-7)/x = 7/9
=> 9x-63 = 7x
=> 2x = 63
=> x = 31.5

So Sachin age is 31.5 - 7 = 24.5

1. The sum of the ages of a father and son is 45 years. Five years ago, the product of their ages was four times the fathers age at that time. The present age of father and son

34,11
35,10
36,9
40,5

Answer: Option C

Explanation:

Let sons age = x years. Then fathers age = (45 - x)years.
(x—5)(45—x—5) = 4(45- x - 5) hence (x—5) = 4 so x = 9
Their ages are 36 years and 9 years.

2. Average age of A and B is 24 years and average age of B, C and D is 22 years. The sum of the ages of A, B, C and D is

90
98
120
Data is not adequate

Answer: Option D

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

Answer: Option A

Explanation:

Let the present age of P and Q be 3x and 4x respectively.
Ten years ago, P was half of Q in age
=> 2(3x – 10) = (4x – 10)

=> 6x – 20 = 4x – 10

=> 2x = 10

=> x = 5

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. In 10 years, A will be twice as old5as B was 10 years ago. If A is now 9 years older than B, the present age of B is

Answer: Option C

Explanation:

Let B's age = x years.
Then, As age = (x+ 9) years.
(x+9+10)=2(x—10)
hence x=39.
Present age of B = 39 years