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 C

Explanation:

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

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

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

Answer: Option D

Explanation:

Let their ages be x and (x + 20) years.
5 (x - 5) = (x + 20 - 5) or 4x = 40 or x = 10.
Their present ages are 30 years and 10 years

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.