Ten years ago. A was half of B in age. If the ratio of their present age is 3 : 4 What will be the total of their present ages?
সমাধান
সঠিক উত্তর: Option D
let, Ten years ago, A was x years old
B was 2x years old
ATQ,
(x + 10)/(2x + 10) = 3/4
⇒ 4x + 40 = 6x = 30
⇒ 6x - 4x = 40 - 30
⇒ 2x = 10
∴ x = 5
total present age = x + 2x + 20
= 3x + 20
= 3 × 5 + 20
= 35 years
B was 2x years old
ATQ,
(x + 10)/(2x + 10) = 3/4
⇒ 4x + 40 = 6x = 30
⇒ 6x - 4x = 40 - 30
⇒ 2x = 10
∴ x = 5
total present age = x + 2x + 20
= 3x + 20
= 3 × 5 + 20
= 35 years
