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. 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

2. Which of following statements are required to answer the Actual age of Abhinav ?
1. Five years ago, Abhinav's age was double that of his son's age at that time.
2. Present ages of Abhinav and his son are in the ratio of 11 : 6 respectively.
3. Five years hence, the respective ratio of Abhinav age and his son's age will become 12 : 7.

1 and 3
2 and 3
Any two of three
None of three

Answer: Option C

Explanation:

From 2nd we get, Present ages of Abhinav and his son is 11x and 6x,

From 1st we get, Abhinav's present age = 2 * Son's age

From 3rd we get, 5 years hence, Abhinav age / Son's age = 12 / 7

From clearly we can get Abhinav age from any of two equations.

3. 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

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 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