# How do you solve the proportion 2/5=x/100?

Dec 13, 2016

$x = 40$

#### Explanation:

One way to do this is to multiply the first fraction by $\frac{20}{20}$

$\frac{2}{5} \cdot \frac{20}{20} = \frac{2 \cdot 20}{5 \cdot 20} = \frac{40}{100}$

Now you have

$\frac{40}{100} = \frac{x}{100}$

Two fractions that have the same denominator are equal if their numerators are equal, so

$40 = x$