$$90 \% ( x - 10 ) = 63$$
$x=80$
$$\frac{9}{10}\left(x-10\right)=63$$
$$\frac{9}{10}x+\frac{9}{10}\left(-10\right)=63$$
$$\frac{9}{10}x+\frac{9\left(-10\right)}{10}=63$$
$$\frac{9}{10}x+\frac{-90}{10}=63$$
$$\frac{9}{10}x-9=63$$
$$\frac{9}{10}x=63+9$$
$$\frac{9}{10}x=72$$
$$x=72\times \frac{10}{9}$$
$$x=\frac{72\times 10}{9}$$
$$x=\frac{720}{9}$$
$$x=80$$
Show Solution
Hide Solution
