Question

# Fifteen years from now, Ravi’s age will be four times his present age. What is Ravi’s present age?

Let Ravi’s present age is $x$ years old.
Then after fifteen years, his age will be $\left( {x + 15} \right)$ years old.
Age after $15$ years $= 4 \times$Present Age,
$\Rightarrow \left( {x + 15} \right) = 4x, \\ \Rightarrow 4x - x = 15, \\ \Rightarrow 3x = 15, \\ \Rightarrow x = 5 \\$
Therefore, Ravi’s present age is $5$ years old.