SOLUTION: To get a B in math Rich must score an average of 80 in five tests. His scores on the first four tests were 80,74,81,and 75. What is the lowest score that Rich can get on the last t

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Question 1025076: To get a B in math Rich must score an average of 80 in five tests. His scores on the first four tests were 80,74,81,and 75. What is the lowest score that Rich can get on the last test and still receive a B.
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
he scored a total of 80 + 74 + 81 + 75 = 310 on the first 4 test.

to get an overall average of 80 on 5 tests, he has to score a total of 5 * 80 = 400 on all 5 tests.

400 - 410 = 90.

he has to score at least a 90 on the last test.

80 + 74 + 81 + 75 + 90 = 400

400 / 5 = average of 80.