# How do you solve the proportion 5/x=10/4?

Jun 17, 2017

$x = 2$

#### Explanation:

This can be solved using cross multiplication. This fraction equation is the same as the following:

$x \times 10 = 5 \times 4$

$x \times 10 = 20$

Divide both sides by $10$

$x \times \frac{\cancel{10}}{\cancel{10}} = \frac{20}{10}$

$x = 2$

Jun 17, 2017

$x = 2$

#### Explanation:

When you have proportions (two fractions equal to each other), cross multiply:
Left Numerator x Right Denominator = Right Numerator x Left Denominator
$\frac{5}{x} = \frac{10}{4}$
$5 \cdot 4 = 10 \cdot x$

Solve:
$5 \cdot 4 = 10 \cdot x$
$20 = 10 x$
$x = 2$