Name ____________________________

Unit 4 Review

Identify the following relationships as directly proportional or inversely proportional. Identify the independent variable and the dependent variable.

1. The height of a candle and the length of time it is burned

2. A person's age and their income

Look at each pair of ratios. Tell whether or not these ratios form a proportion.

3. $\frac{1}{2}$ and $\frac{4}{8}$

4. $\frac{3}{7}$ and $\frac{6}{14}$

Use proportional reasoning to find the value of the variable in each proportion.

5. $\frac{1}{4} = \frac{a}{20}$

6. $\frac{15}{30} = \frac{x}{2}$

7. The current standard for low-flow showerheads is 2.5 gallons per minute. Calculate how long it would take to fill a 30-gallon bathtub using such a showerhead to supply the water.

8. The diameter of a circle is directly proportional to its radius. If a circle with a 2-inch diameter has a circumference of approximately 6.28 inches, what is the circumference of a 15-inch circle?

9. Land in Wisconsin is for sale to property investors. A 232-acre lot is listed for sale for $200,500. Assuming the same price per acre, how much would a 60-acre lot sell for?

10. Given the table below, determine the direct variation function and then graph.

Hours	Distance
0
1
2
3
4

Use the given and values to write a direct variation equation and find given that y=2 .

11. x=5,y=4

12. x=18,y=3

13. Based on her weight and pace, Kate burns 586 calories when she runs five miles. How many calories will she burn if she runs only 3 miles? How many miles (to the nearest mile) does she need to run each week if she wants to burn one pound (3500 calories) of body fat each week?

Write an equivalent rate for each rate.

14. two for $10.00

15. three for $15.00

Find the unit rate.

16. 10 feet in two minutes

17. 12 pounds in six weeks

Determine whether each is equivalent or not.

18. 60 units in three minutes and 80 units in four minutes

19. $16 for eight pounds and $22 for ten pounds

20. Max paid $45 for 15 gallons of gasoline. What was the cost per gallon of gasoline?

21. Mr. Brown paid $8.28 for 12 cans of green beans. Express this cost as a unit price.

Tell if the slope of the line shown is positive, negative, zero, or undefined.