Seven years ago, the ratio of the ages of A and B was 4 : 5 . Eight years hence, the ratio of the ages of A and B will be 9 : 10. what is the sum of their present ages in years?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 41.
Seven years ago the ratio of ages of A and B = 4 : 5
After 8 years from the present the ratio of ages of A and B = 9 : 10
Seven years ago the ratio of ages of A and B = 4x : 5x
Ratio of Present ages of A and B = 4x + 7 : 5x + 7
After 8 years the ratio of ages of A and B = (4x + 7 + 8) : (5x + 7 + 8) = 9 : 10
ATQ -
(4x + 15) : (5x + 15) = 9/10
40x + 150 = 45x + 135
5x = 15
x = 3
Sum of present ages of A and B = (4 × 3 + 7) + (5 × 3 + 7) = (19 + 22) = 41 years