SOLUTION: I have been trying to solve this question but I'm not following. A student earned a grade of 80 percent on a math test and got 32 correct how many problems did the student get wro

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Question 1012611: I have been trying to solve this question but I'm not following. A student earned a grade of 80 percent on a math test and got 32 correct how many problems did the student get wrong.

Found 3 solutions by rothauserc, MathTherapy, fractalier:
Answer by rothauserc(4718)   (Show Source):
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80 / 32 = 100 / x
80x = 3200
x = 40
therefore there were 40 questions on the test and
the student got 8 wrong

Answer by MathTherapy(10552)   (Show Source):
You can put this solution on YOUR website!

I have been trying to solve this question but I'm not following. A student earned a grade of 80 percent on a math test and got 32 correct how many problems did the student get wrong.

Let number of incorrect answers be I
Then number of questions on test = I + 32
We then get:
.8(I + 32) = 32 ------ Cross-multiplying
.8I + 25.6 = 32
.8I = 32 - 25.6
.8I = 6.4
I, or number of incorrect answers = , or

Answer by fractalier(6550)   (Show Source):
You can put this solution on YOUR website!
If the student got 80% correct and got 32 questions correct, then 80% of the total questions must be 32. Call the total, x. Then we can write
(.80)x = 32
x = 40 questions total
Thus the student missed 40-32 = 8 questions.