Question

5years ago a:b=3:1 ,5 yrs hence a:b=11:5 find the present age of a

Answer 1

let the ratio be X

so , before 5 years , a:b = 3x : x

today , a:b = 3x + 5 : x + 5

after 5 years , a:b = 3x + 10 : x + 10

now , according to given condition ,


3x + 10 : x + 10 = 11 : 5


3x + 10 11
---------- = ------
x + 10 5


5 ( 3x + 10 ) = 11 ( x + 10 )

15x + 50 = 11x + 110

15x - 11x = 110 - 50

4x = 60

X = 15

therefore present age of a = 3x +5

= 3 × 15 + 5

= 50 years