SOLUTION: Currently, 1/4 of the members of a local club are boys, and there are 80 members. If no one withdraws from the club, what is the minimum number of boys that would need to join to m

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: Currently, 1/4 of the members of a local club are boys, and there are 80 members. If no one withdraws from the club, what is the minimum number of boys that would need to join to m      Log On


   

Question 984561: Currently, 1/4 of the members of a local club are boys, and there are 80 members. If no one withdraws from the club, what is the minimum number of boys that would need to join to make the club 1/3 boys?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +n+ = the number of boys that
are needed to join
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Currently, +%281%2F4%29%2A80+=+20+ are boys
+%28+20+%2B+n+%29+%2F+%28+80+%2B+n+%29+=+1%2F3+
+3%2A%28+20+%2B+n+%29+=+80+%2B+n+
+60+%2B+3n+=+80+%2B+n+
+2n+=+80+-+60+
+2n+=+20+
+n+=+10+
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If 10 boys join the club, there will
be 1/3 boys
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check:
+%28+20+%2B+n+%29+%2F+%28+80+%2B+n+%29+=+1%2F3+
+%28+20+%2B+10+%29+%2F+%28+80+%2B+10+%29+=+1%2F3+
+30+%2F+90+=+1%2F3+
+1%2F3+=+1%2F3+
OK