Ratios, Rates, and Unit Rates

Ratios, Rates, and Unit Rates

What is the ratio of white light bulbs to yellow light bulbs?

Open Ended

What do you know about ratios? If you don't know anything, it is fine.

Ratios

• You always write ratios the way it is stated.

• For example: What is the ratio of snow-cones to chocolate? - So you would write it snow-cones : chocolate

Fill in the Blank

What is the ratio of books to pens? Using one of the 3 ways we have learned to write a ratio, you would write this as ________.

Open Ended

What do you know about equivalent ratios? If you don't know anything it is fine.

Ratios

• Comparison of 2 quantities

• Can be same or different units

• Written in 3 ways - 2 to 3, 2:3, 2/3

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• The number on the left is the first number

• The number on the right is the second number

Equivalent Ratios

• Ratios that make the same comparison of numbers

• To get an equivalent ratio, multiply both numbers by the same number or divide both numbers by the same number

The ratio of adults to children is 2 to 5

• 2 adults, 5 children

• 4 adults, 10 children

• 20 adults, 50 children

Open Ended

What do you think we could compare equivalent ratios to? Like what other topic?

Multiple Select

Pick 2 ratios that are equivalent to 9:7

• 81:72

• 81:49

• 36:27

• 18:14

Open Ended

What do you know about rates? If you don't know anything it is fine.

Rates

• Compares 2 quantities

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

• 
  

Open Ended

What do you know about unit rates? If you don't know anything it is fine.

Unit Rates

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

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

• Unit rates "play off" of rates. Rates are just the start of the unit rate.

Example 1

Brian watches 2 dogs for 7 days. He has a 128 oz bag of dog food. Buster eats 20.5 oz in 2 days and Roxy eats 22.5 oz in 3 days. Does Brian have enough dog food for 7 days?

Example 2

Steve drives 78 miles on 3 gallons of gas. Find the miles per gallon.

Multiple Choice

A skydiver falls 144 feet in 3 seconds. How far does the skydiver fall per second?

• 47

• 48

• 44

• 49

Multiple Select

What is the ratio of pumpkins to cabbage? Select all that apply.

• 2:7

• 7:2

• 2 to 7

• 7 to 2

• 7/2

Multiple Choice

The ratio of tomatoes to red apples is 2:5. If there are 20 tomatoes then how many red apples are there?

• 20

• 15

• 50

• 55

Poll

How do you think you are with ratios, rates, and unit rates?

• I get it

• I kind of get it

• I don't get it

• I have no clue what we just learned

Match

Match the following vocabulary terms to their definitions.

• comparison of two quantitities

• a comparison of two quantities with units

• a comparison of two quantities with units when the quantity in the denominator is 1

ratio

rate

unit rate

• ratio

• rate

• unit rate