Question

17. At present, the ratio of the ages of A to B is 1 : 2 and
that of A to C is 3: 4. Twelve years ago, the sum of
the ages of A, B and C was 146 years. What is the
present age of B?
(1) 78 years (2) 96 years
(3) 84 years
(4) 60 years (5) 90 years​

Answer 1

Answer:

ration of A:B = 1:2( multiply it by 3 we get 3:6)

A:C = 3:4

so age of A = 3x, B = 6x C = 4x so

A:B:C = 3:6:4

12 years ago age of A is 3x-12

B is 6x-12

c is 4x-12

so (3x-12)+(6x-12)+(4x-12) =146

so 13x-36= 146

13x=146+36

13x= 182

x = 182/13=14

so age of B is 6x=6×14= 84