Solving Proportions

Front

What is a proportion?

Back

A proportion is an equation that states that two ratios are equal.

Front

How do you solve a proportion?

Back

To solve a proportion, cross-multiply the terms and then isolate the variable.

Front

What does cross-multiplication mean?

Back

Cross-multiplication involves multiplying the numerator of one ratio by the denominator of the other ratio.

Front

If \( \frac{a}{b} = \frac{c}{d} \), what is the cross-multiplication equation?

Back

The cross-multiplication equation is \( a \cdot d = b \cdot c \).

Front

Solve the proportion: \( \frac{2}{3} = \frac{x}{12} \)

Back

x = 8

Front

Solve the proportion: \( \frac{5}{10} = \frac{y}{20} \)

Back

y = 10

Front

What is the value of x in the proportion \( \frac{13}{49} = \frac{66}{x} \)?

Back

x = 248.77

Front

What is the value of b in the proportion \( \frac{7}{98.8} = \frac{36.1}{b} \)?

Back

b = 509.53

Front

Solve the proportion: \( \frac{3}{4} = \frac{x}{20} \)

Back

x = 15

Front

What is a ratio?

Back

A ratio is a comparison of two quantities by division.