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3 years ago

Mark had 14 problems wrong on his test. his score was 72% correct. how many problems were on the test?

1 answer:

4 0

Let x = number of problems on test
If he got 14 wrong, then x - 14 is the number correct.
$\frac{x-14}{x} = .72
$
x - 14 = .72x
.28x - 14 = 0
.28x = 14
x = 50

The test consisted of 50 problems.

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