# Question #2520d

Oct 22, 2017

$y = 10$

#### Explanation:

$\frac{4}{8} = \frac{5}{y}$

Multiply both sides by $8$.

${\textcolor{red}{\cancel{\textcolor{b l a c k}{8}}}}^{1} \times \frac{4}{\textcolor{red}{\cancel{\textcolor{b l a c k}{8}}}} ^ 1 = \frac{5}{y} \times 8$

Simplify.

$4 = \frac{40}{y}$

Multiply both sides by $y$.

$4 y = \frac{40}{\textcolor{red}{\cancel{\textcolor{b l a c k}{y}}}} ^ 1 \times {\textcolor{red}{\cancel{\textcolor{b l a c k}{y}}}}^{1}$

Simplify.

$4 y = 40$

Divide both sides by $4$.

$y = \frac{40}{4}$

$y = 10$

Check the proportions (ratios) on both sides of the equation.

$\frac{4}{8} = 0.5$

$\frac{5}{10} = 0.5$

$0.5 = 0.5$