Ratios, Proportions, and Similar Figures

Front

What is a ratio?

Back

A ratio is a comparison of two quantities by division, expressed as 'a to b' or a:b.

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 set the products equal to each other.

Front

What does it mean for two figures to be similar?

Back

Two figures are similar if they have the same shape but not necessarily the same size, and their corresponding angles are equal while their corresponding sides are in proportion.

Front

If a recipe requires 2 cups of milk for every 3 cups of flour, what is the ratio of milk to flour?

Back

The ratio of milk to flour is 2:3.

Front

If Carl spends $5 on movies for every $15 on video games, what is the ratio of movies to video games?

Back

The ratio of movies to video games is 1:3.

Front

How do you find a missing value in a proportion?

Back

To find a missing value in a proportion, set up the equation using cross-multiplication and solve for the unknown.

Front

What is the formula for finding the scale factor between two similar figures?

Back

The scale factor is found by dividing the length of a side of one figure by the corresponding side of the other figure.

Front

If two triangles are similar and one has a side length of 6 cm and the corresponding side of the other triangle is 9 cm, what is the scale factor?

Back

The scale factor is 6:9 or 2:3.

Front

How do you determine if two ratios are equivalent?

Back

Two ratios are equivalent if their cross products are equal.