Question

The sum of ages of Sania and Yogesh is 50 years. If now Sania is twice as old as Yogesh was 5 years ago, then present age of Sania is :

Accepted Answer

D. Let Sania's age be $S$ and Yogesh's age be $Y$. $S + Y = 50 \implies Y = 50 - S$ Given $S = 2(Y - 5)$. Substitute $Y$: $S = 2(50 - S - 5) = 2(45 - S) = 90 - 2S \implies 3S = 90 \implies S = 30$ years.

Age problem linear equations

Explanation

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