SOLUTION: If I have an average of a 72 and I will take a test that's worth 20%. What grade do I need to get on my test in order for my average to be 80 or above?

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Question 817232: If I have an average of a 72 and I will take a test that's worth 20%. What grade do I need to get on my test in order for my average to be 80 or above?
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
if the test is worth 20% then the present average is worth 80%
.80*72+.2x>=80
57.6 +.2 x>=80
your 72 average is only worth 57.6 you need to get 20% of the test that is worth 22.4
You will need to get 112 on the test
to get 75 you will need 87
with a grade of 100 on the test you would get a total 77.6