The rates are classified as follows
8. not proportional
9. proportional
10. not proportional
11. proportional
12. not proportional
13. not proportional
Solving Proportions:
14. y = 3
15. c = 12
16. z = 1
17. t = 1.21
18. a = 18
19. y = 0.45
How to solve proportions
A proportion is an equation that states that two ratios are equal.
The proportions are solved by cross multiplying and simplifying
14. 4/12 = y/9
y = 9 * 4/12
y = 3
15. 6/18 = 4/c
6c = 18 * 4
c = 18 * 4/6
c = 12
16. 7/z = 84/12
84z = 12 * 7
z = 12 * 7/84
z = 1
17. 11/t = 100/11
100t = 11 * 11
t = 11 * 11/100
t = 1.21
18. 0.9/0.5 = a/10
0.5a = 0.9 * 10
a = 0.9 * 10/.5
a = 18
19. 14/1.5 = 4.2/y
14y = 1.5 * 4.2
y = 1.5 * 4.2 / 14
y = 0.45