Question

A college professor 115 papers to grade. The professor determined that the equation p = -10t + 115 can be used to predict the number of papers left to grade p, after t hours. Can the professor finish grading all of the papers in 7.5 hours?

Answer 1

No

Explanation:

Plug in 7.5 as t into the equation, and solve:

p = -10t + 115

p = -10(7.5) + 115

p = -75 + 115

p = 40

This means in 7.5 hours, he will still have 40 papers left to grade.

So, he will not be able to finish grading in 7.5 hours.