Rates, Ratios, and Proportions

Front

What is a rate?

Back

A rate is a ratio that compares two different kinds of quantities, often expressed as a quantity per unit of another quantity, such as miles per hour.

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

What is a proportion?

Back

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

Front

How do you find the unit rate?

Back

To find the unit rate, divide the quantity by the number of units. For example, if you drive 92 miles using 4 gallons of gas, the unit rate is 92 ÷ 4 = 23 miles per gallon.

Front

If a watermelon costs $3.24 for 3 pounds, what is the cost per pound?

Back

$1.08

Front

Melissa drives 240 miles in 5 hours. What is her average rate of speed?

Back

48 mph

Front

In an animal shelter, the ratio of dogs to cats is 5 to 3. If there are 25 dogs, how many cats are there?

Back

15 cats

Front

How many ways can you write a ratio?

Back

3 ways: as a fraction, with a colon, or with the word 'to'.

Front

What is the formula for calculating a rate?

Back

Rate = Quantity / Time.

Front

What does it mean if two ratios are in proportion?

Back

It means that the two ratios are equivalent, meaning they represent the same relationship between quantities.