SOLUTION: if there were 90 questions on a test, and amber recieved a 95%, how many questions did she answer incorrectly?

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Question 958628: if there were 90 questions on a test, and amber recieved a 95%, how many questions did she answer incorrectly?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
%2890-X%29%2F90=95%2F100
90-X=8550%2F100
90-X=171%2F2
X=180%2F2-171%2F2
X=9%2F2
So Amber either got 4 or 5 wrong.
If she got 4 wrong,
86%2F90=95.56
which would round up to 96.
If she got 5 wrong,
85%2F90=94.44
which would round down to 94.
So Amber couldn't have gotten a 95%.