1. Ratios

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

3. Ratios can be written in 3 ways:
Using a colon
2:3
As a fraction
2 3
With the word, “to”
2 to 3

4. Ratios can show three scenarios:
Part to part
Part to whole
Whole to part

5. Part to Part
Blue to Yellow
5: to 4

6. Part to Whole
Blue to Total
5: to 9

7. Whole to Part
Total to Yellow
9: to 4

8. 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

9. 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 whole)
6 24
Total to blue (whole to part)
24 18

10. 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 whole)
5 to 34
Total to Adventure (whole to part)
34 to 9

11. Equivalent Ratios 2:3 is the same as 4:6 or 6:9
9 to 5 is the same as 18 to 10 or 81 to 45

12. Draw the following ratios, using squares and circles:
4:4
5 9
9 to 3

13. Write the following ratios in all three ways:

14. Write an equivalent ratio
70:35
8 6
14 to 15