Rates, Unit Rates & Proportions

Front

What is a unit rate?

Back

A unit rate is a comparison of two different quantities where one of the quantities is expressed as one unit. For example, if you earn $18 for 1 hour of work, the unit rate is $18 per hour.

Front

How do you calculate the unit rate?

Back

To calculate the unit rate, divide the total amount by the number of units. For example, if you have $90 for 5 hours, the unit rate is $90 ÷ 5 = $18 per hour.

Front

What is the unit price of an item?

Back

The unit price is the cost of one item or one unit of a product. For example, if 5 boxes of candy cost $12.54, the unit price of one box is $12.54 ÷ 5 = $2.50.

Front

If 3 pounds of hamburger costs $6, what is the cost of 10 pounds?

Back

If 3 pounds cost $6, then 1 pound costs $6 ÷ 3 = $2. Therefore, 10 pounds will cost 10 × $2 = $20.

Front

When are unit rates useful?

Back

Unit rates are useful when you want to compare prices or quantities to determine which is a better deal.

Front

If Justin can type 408 words in 4 minutes, how many words can he type per minute?

Back

To find out how many words he can type per minute, divide 408 words by 4 minutes: 408 ÷ 4 = 102 words per minute.

Front

What is a proportion?

Back

A proportion is an equation that states that two ratios are equal. For example, if a/b = c/d, then a, b, c, and d are in proportion.

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How do you solve a proportion?

Back

To solve a proportion, cross-multiply and then divide. For example, if a/b = c/d, then a × d = b × c.

Front

What is the difference between a rate and a unit rate?

Back

A rate is a comparison of two quantities with different units, while a unit rate is a rate where the second quantity is one unit.

Front

If a car travels 150 miles in 3 hours, what is its speed in miles per hour?

Back

To find the speed, divide the distance by the time: 150 miles ÷ 3 hours = 50 miles per hour.