Question

In your​ class, you have scores of 73,85,76, and 92 on the first four of five tests. To get a grade of Upper C, the average of the first five tests scores must be greater than or equal to 70 and less than 80.

a) Solve an inequality to find the least score you can get on the last test and still earn a Upper C.

b) What score do you need if the fifth test counts as two​ tests?

Answer 1

consider the total points. The total so far is 326. If the last grade is x, then you need

350 <= 326+x < 400
24 <= x < 74

If the 5th test counts as two, then it's like having six scores:

420 <= 326+2x < 480
94 <= 2x < 154
47 <= x < 77

Answer 2

46