Question

Find a number whose double is $45$ greater than its half.

Answer 1

Let the required number $=x$

Double of it $=2x$

and half of it $=\frac{x}{2}$

According to the condition

$\Rightarrow 2x-\frac{x}{2}=45$

$\Rightarrow \frac{4x-x}{2}=45$

$\Rightarrow \frac{3}{2}x=45$

$\Rightarrow x=\frac{45\times 2}{3}=30$

$\therefore$ Required number $=30$

Check : $2\times 30-\frac{1}{2}\times 30$

$=60-15=45$, which is given

$\therefore$ Our answer is correct.