Answer
$r=10$
Work Step by Step
We are given that $\frac{4r}{5}-\frac{r}{10}=7$. First, we can multiply each term by 10. Since this is the least common denominator of each term, this will eliminate all fractions from the equation.
$\frac{4r}{5}\times10-\frac{r}{10}\times10=7\times10$
$8r-r=70$
Group like terms on the left side.
$7r=70$
Divide both sides by 7.
$r=10$
