age problem | Engineering Mathematics and Sciences

Peter is 36 years old. Peter is twice as old as Jun was when Peter was as old as Jun is now. How old is Jun?

Solution:

Let $x$ be the age of Jun now.

Consider the following table:

[wpdatatable id=1]

Therefore,

\begin{align*} 36-x & =x-\frac{x}{2} \\ 36-x & = \frac{x}{2} \\ 36 & = \frac{x}{2}+x \\ 36 & = \frac{3x}{2} \\ x & = \frac{36\left( 2 \right)}{3} \\ x & = 24 \ \text{years old} \ \qquad \ \color{DarkOrange} \left( \text{Answer} \right) \end{align*}

Jun is 24 years old now.