Ratios and Proportions

Front

What is a Ratio?

Back

A ratio is a comparison of two quantities.

Front

What is a Proportion?

Back

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

Front

How do you determine if two ratios form a proportion?

Back

Two ratios form a proportion if their cross products are equal.

Front

What is a Unit Rate?

Back

A unit rate is a ratio that compares a quantity to one unit of another quantity.

Front

If 30 cm of snow falls in 6 hours, what is the unit rate of snow per hour?

Back

5 cm of snow per hour.

Front

What is the scale in a scale drawing?

Back

The scale is the ratio of the length in the drawing to the actual length.

Front

If a scale drawing uses a scale of 4 cm:9 ft, how do you find the actual length of an object?

Back

Use the scale to set up a proportion and solve for the actual length.

Front

If a billboard in a drawing is 11 cm long, how long is it in reality if the scale is 4 cm:9 ft?

Back

24.75 ft.

Front

What is the first step in solving a proportion?

Back

Cross-multiply the ratios.

Front

If x/3 = 2, what is the value of x?

Back

x = 6.