Ratios and Proportions

Front

What is a ratio?

Back

A ratio is a comparison of two quantities by division, showing how many times one value contains or is contained within the other.

Front

How do you find the unit rate?

Back

To find the unit rate, divide the total amount by the number of units. For example, if 3 pounds of granola cost $3.75, the unit rate is $3.75 ÷ 3 = $1.25 per pound.

Front

What does it mean for two quantities to be in proportion?

Back

Two quantities are in proportion if they have a constant ratio or rate. This means that as one quantity changes, the other changes at a consistent rate.

Front

How do you solve a problem involving scale drawings?

Back

To solve a scale drawing problem, set up a proportion using the scale and the measurements given. For example, if the scale is 4 cm:9 ft and the drawing is 11 cm, set up the proportion 4 cm/9 ft = 11 cm/x ft and solve for x.

Front

What is the formula for finding a missing value in a proportion?

Back

The formula is a/b = c/d, where a and b are the first ratio, and c and d are the second ratio. Cross-multiply to find the missing value.

Front

What is a proportional relationship?

Back

A proportional relationship is one where two quantities maintain a constant ratio. If one quantity doubles, the other also doubles.

Front

How can you express a ratio in simplest form?

Back

To express a ratio in simplest form, divide both terms of the ratio by their greatest common factor (GCF). For example, the ratio 10:5 can be simplified to 2:1.

Front

What is the difference between a ratio and a fraction?

Back

A ratio compares two quantities, while a fraction represents a part of a whole. Ratios can be written in different forms, such as a:b or a/b.

Front

How do you determine if a table represents a proportional relationship?

Back

To determine if a table represents a proportional relationship, check if the ratios of corresponding values are constant.

Front

What is the price per unit?

Back

The price per unit is the cost of one unit of a product. It is calculated by dividing the total cost by the number of units.