Answer:
Choice C
Explanation:
$80 to 5 hours
Divide both numbers by 5 to find the unit rate:
$16 to 1 hour, or 16 to 1
For x hours, the pay, y, is y = 16x.
Choice A is true.
Look at choice B.
When x = 5, y = 80.
This is correct because we are given that information.
The process is to multiply the hours by 16.
For x hours, y = 16x (from choice A)
For x = 7, y = 7 * 16
Choice B works.
Look at choice C.
We need a proportion. The left side is the ratio 80/5, meaning $80 for 5 hours of work. Notice that the first number in the ratio is dollars, and the second number is hours. Now we need another ratio written in the same order to set up a proportion. x dollars is to 7 hours. This is the ratio x/7. The correct proportion is
80/5 = x/7
Choice C is 80/5 = 7/x
Choice C is incorrect.
Look at choice D.
The graph shows that for 5 hours, the pay is $80, so by looking up x = 7, you can find the correct amount of pay.
Choice D works.
Answer: Choice C