Question
The ratio of present ages of
Rohan to his father is 2:7, and the ratio of present ages of Rohan to his mother is 3:10. If Rohan's father is 6 years older than his mother, find Rohan's current age.Solution
ATQ,
Let Rohan's present age be ‘x’ years. Then, Rohan’s father’s age will be ‘7x/2’ years. Also, let Rohan’s present age be ‘3y’ years. So, Rohan’s mother’s present age will be ‘10y’ years. We have, x = 3y and 7x/2 − 6 = 10y. Substitute x = 3y: 7(3y)/2 − 6 = 10y. Simplifying, (21y/2) − 6=10 Multiply the equation by 2 to eliminate the fraction: 21y − 12 = 20y. Simplifying further: 21y − 20y = 12, y = 12. So, Rohan’s present age = x = 3y = 36 years.
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