Problem:
Shauna takes five tests, each worth a maximum of points. Her scores on the first three tests are and . In order to average for all five tests, what is the lowest score she could earn on one of the other two tests?
Answer Choices:
A.
B.
C.
D.
E.
Solution:
To minimize one of the scores, we have to maximize the other score. Assume that Shauna gets a on her fourth test. The sum of the tests is then . For an average of , Shauna's test scores must add to . This means that she needs to get a on her last test.
Thus, the correct answer is .
Answer: .
The problems on this page are the property of the MAA's American Mathematics Competitions