1. Do Now
The ratio of men to women on a cruise is 6 to 8. If there are 168 people on the cruise, how many women are there?

2. More Difficult Proportions1) 2)

3. 3) 4)

4. 5) 6)

5. Direct Variation
If two variables vary directly, their ratio is constant.
In other words, the variables increase or decrease proportionally.
As one increases, so does the other.
As one decreases, so does the other.

6. Examples Find each value if x and y vary directly.
If y = 4 when x = 2, find y when x = 16.
2) If y = 9 when x = – 3, find x when y = 6.

7. If y = – 4.8 when x = – 1.6, find x when

8. Quiz Topics Solving Equations for a Variable Ratios and Proportions
Word Problems
Proportions with Distributing
Direct Variation

9. If Mice Owned Computers...