An Introduction to Ratios!

A Ratio is… A comparison between two quantities For every x units of one quantity, there are y units of another

3 Ways to Display Ratios Using a colon Example: 2:3 As a fraction Example: 𝟐 𝟑 With the word, “to” Example: 2 to 3

Ratios Show Three Scenarios Part to part Part to whole Whole to part

Scenario #1: Part to Part Blue to Yellow 5:4 𝟓 𝟒 5 to 4

Scenario #2: Part to Whole Blue to Total 5:9 𝟓 𝟗 5 to 9

Scenario #3: Whole to Part Total to Yellow 9:4 𝟗 𝟒 9 to 4

Ratio Word Problem Example #1: A sixth grade basketball team has 3 centers, 5 forwards, and 6 guards. Write a ratio for each comparison using a colon: Forwards to guards (part to part) 5:6 Centers to total (part to whole) 3:14 Total to guards (whole to part) 14:6

Ratio Word Problem Example #2: Martine’s quilt is made of 6 red squares and 18 blue squares. Write a ratio for each comparison using the fraction. Red to blue (part to part) 𝟔 𝟏𝟖 Red to total (part to total) 𝟔 𝟐𝟒 Total to blue (total to part) 𝟐𝟒 𝟏𝟖

Ratio Word Problem Example #3: Gene has a movie collection. He has 9 Adventure movies, 8 Horror, 5 Sci-Fi, and 12 Comedy. Write a ratio for each comparison using the word, “to.” Horror to comedy (part to part) 8 to 12 Sci-Fi to total (part to total) 5 to 34 Total to Adventure (total to part) 34 to 9

Equivalent ratios are the same as equivalent fractions 2:3 is the same as 4:6 or 6:9 1 2 is the same as 5 10 or 30 60 9 to 5 is the same as 18 to 10 or 81 to 45

Practice – You Try! Directions: Draw the following ratios, using squares and circles: 4:4 𝟓 𝟗 9 to 3

Practice – You Try! Directions: Write the following ratios in all three ways.

Practice – You Try! Directions: Write an equivalent ratio. 70:35 𝟖 𝟔 14 to 15