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Question 80555: A professor started a project with a group of students, 60% of whom were boyus. Due to some unavoidavle reason, six girls couldn't turn up, so the proessor had to make some changes in the gorup. He admitted 6 boys. In doing so, the percentage of boyus in the project increased to 75%. The the number of boys and girls in involved in the project initially.
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! A professor started a project with a group of students, 60% of whom were boys. Due to some unavoidable reasons, six girls couldn't turn up, so the professor had to make some changes in the group. He admitted six boys. In doing so, the percentage of boys in the project increased to 75%. Find the number of boys and girls involved in the project initially.
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Let t = total number of students,
.6t = number of boys originally
:
(.6t + 6) = actual number of boys (which the problem says became 75%)
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From all this we have one simple equation:
.6t + 6 = .75t
.6t - .75t = -6
-.15t = -6
t = -6/-.15
t = +40 kids
:
.6 * 40 = 24 boys originally
.4 * 40 = 16 girls "
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