SOLUTION: In an exam, 80 problems were given and al the problems carried equal marks. If a boy had 28 problems correct, what percentage did he get? And in order to pass this exam, It's neces

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Question 1110380: In an exam, 80 problems were given and al the problems carried equal marks. If a boy had 28 problems correct, what percentage did he get? And in order to pass this exam, It's necessary to answer at least 45% of the problem correctly. What was the lowest number of correct answers needed to pass?
Answer by Cromlix(4381)   (Show Source): You can put this solution on YOUR website!
Hi there,
28 problems out of 80 correct
28/80 * 100 = 35% [* means times]
He requires 45%
x/80 * 100 = 45
x/80 = 45/100
x/80 = 0.45
x = 0.45 * 80
x = 36
The boy requires to get at least 36 answers right out of 80
to attain 45%
Hope this helps :-)

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