1. Ratios and Rates

2. Ratios and Rates
ratio – a comparison of two numbers by division written in several different forms.

3. Ratios and Rates
rate – a ratio that compares different kinds of units by division to obtain a unit rate or rate per unit.

4. Ratios and Rates
The order of the numbers in a ratio should match the order of the words in a ratio.
apples to oranges
2 to 3

5. Ratios can be written in several different ways.
Ratios and Rates
Ratios can be written in several different ways.
red to white
3 to 1
3 : 1
3/1

6. Ratios and Rates Ratios can show comparisons between: part to part
red to green
1 to 2
green to red
2 to 1

7. Ratios and Rates Ratios can show comparisons between: part to whole
red to whole
1 to 3
green to whole
2 to 3

8. Ratios and Rates Ratios can show comparisons between: whole to part
whole to red
3 to 1
whole to green
3 to 2

9. Ratios and Rates 1/8 Compare octagon to all shapes 1 out of 8 1 : 8

10. Ratios and Rates
Compare all shapes to trapezoid
8/1
8 to 1
8 : 1

11. Ratios and Rates
Compare pentagons to hexagons
2/3
2 to 3
2 : 3

12. Ratios and Rates Give each ratio in three forms.
8 roses out of 24 flowers
8 to 24
8 : 24
3 dogs out of 12 animals
3 to 12
3 : 12

13. Ratios and Rates
A ratio in fraction form can be expressed in simplest form by dividing the numerator and denominator by a common factor.
÷ 8
÷ 3 = =
÷ 8
÷ 3

14. Ratios and Rates
To express a ratio as a rate per unit, write the ratio as a fraction and then divide the numerator by the denominator.
395 miles in 5 hours
miles
miles
79 miles per hour =
hours
hours

15. Ratios and Rates Express each ratio as a rate.
5 inches of rain in 30 days
÷ 5 =
inch of rain per day
÷ 5
120 words in 3 minutes
40 words per minute
words =
per minute