Ratio, Rate, Unit Rate

Ratios, Rates & Unit Rates

​

Poll

A ratio is

• compares 2 quantities measured in different units

• a comparison of 2 quantities

• has a denominator of one

Ratios

The ratio of adults to children is 2 to 5. What does this mean?

Ratio

• comparison of two quantities

• can be same or different units

• written in 3 ways ~ 2 to 3, 2:3, 2/3

For every 2 adults, there are 5 children.

Ratios

• 2 adults, 5 children

• 4 adults, ? children

• ? adults, 50 children

Multiple Choice

Ratio of cats to dogs?

• 5:3

• 3:5

• 1 2/3

Multiple Choice

Ratio of football jerseys to cartoon characters?

• 3 to 2

• 2 : 3

• 2 : 5

Poll

A rate is

• compares 2 quantities measured in different units

• a comparison of 2 quantities

• has a denominator of one

Rate

• compares two quantities

• measured in different units....mi/hr, price/pound

Poll

A unit rate

• compares 2 quantities measured in different units

• a comparison of 2 quantities

• has a denominator of one

Unit Rate

• a rate with a denominator of 1 (unit means 1)

• Ex. Shelby drove 70 miles/1 hr or 70 mph

​Remember that when you divide fractions, the rule is multiply by the reciprocal. (Keep, Change, Flip)

Open Ended

Devin drove 180 miles in 3 hrs. Why is this an example of a rate but not a unit rate?

Open Ended

How can we change 180 miles/3 hrs to a unit rate?

Multiple Choice

Find the unit rate

$46.25 in 5 hrs

• $231.25

• $9.25

• $0.77

• $46.25

Multiple Choice

Find the unit rate:

$78.75 in 9 hrs

• $78.75

• $708.75

• $1.31

• $8.75

Multiple Choice

Find the unit rate:

308 miles on 11 gallons of gasoline

• 28 mpg

• 0.39 mpg

• 3,388 mpg

• 308 mpg

Using Unit Rates

Brian agrees to watch his neighbors dogs for 7 days. His neighbor provided a 128 oz bag of dog food for Buster and Roxy (the 2 dogs). If Buster eats 20.5 oz in 2 days and Roxy eats 22.5 oz in 3 days, does Brian have enough food to feed the dogs all 7 days? Explain.

​It is ok to get a decimal or a fraction when you do this. Look at the examples below

Multiple Choice

Food Lion has a 2 pound bag of almonds for $21.98. Aldi has a 3.5 pound bag of almonds for $30.25. Which store is the least expensive per oz for the almonds and by how much?

• Food Lion,$ 2.35 less

• Food Lion, $10.99 less

• Aldi, $2.35 less

• Aldi, $8.64 less

You will have some unit rates where you are asked to work with mixed numbers as shown on the left.

When given mixed numbers turn them into improper fractions before dividing.

Remember when you divide fractions follow the Keep Change Flip pattern. ​

Example with Complex Fractions

Some text here about the topic of discussion