Ratio of the present age of Mike to the age of Mahira after 6 years is 3:4 and the average of the present age of Mike and Mahira is equal to the age of Max after 6 years. If Mike is 4 years elder than Max, then find the difference between the age of Mahira before 6 years and the present age of Max.
a) 10 years
b) 2 years
c) 5 years
d) 8 years
e) None of these
Sol:
Present age of Mike = 3x
Present age of Mahira = 4x – 6
Max + 6 = (3x + 4x – 6)/2 = (7x – 6)/2 = 3.5x – 3
Max = 3.5x – 9
Present age of Max = 3.5x – 9
3x – (3.5x – 9) = 4
-0.5x + 9 = 4
0.5x = 5
x = 10
Present age of Mahira = 4 * 10 – 6 = 34 years
Present age of Max = 3.5 * 10 – 9 = 26 years
Required difference = (34 – 6) – 26 = 28 – 26 = 2 years