Proportions

Front

What is a proportion?

Back

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

Front

How do you solve for an unknown in a proportion?

Back

Cross-multiply the known values and then solve for the unknown.

Front

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

Back

The ratio of sugar to flour is 2:3.

Front

What is the unit rate?

Back

The unit rate is a comparison of two different quantities when they are combined together, expressed as a quantity of one.

Front

If a car travels 60 miles in 1 hour, what is the speed in miles per minute?

Back

The speed is 1 mile per minute.

Front

How do you find the total cost for a larger group if you know the cost for a smaller group?

Back

Multiply the cost per person by the number of people in the larger group.

Front

What is the relationship between ratios and proportions?

Back

Ratios compare two quantities, while proportions show that two ratios are equal.

Front

If the ratio of cats to dogs is 4:5 and there are 20 cats, how many dogs are there?

Back

There are 25 dogs.

Front

What is a scale factor?

Back

A scale factor is a number that scales, or multiplies, some quantity.

Front

If a recipe is doubled, how do the ingredients change?

Back

All ingredients are multiplied by 2.