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1991 AJHSME Problems/Problem 23

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Problem

The Pythagoras High School band has 100 female and 80 male members. The Pythagoras High School orchestra has 80 female and 100 male members. There are 60 females who are members in both band and orchestra. Altogether, there are 230 students who are in either band or orchestra or both. The number of males in the band who are NOT in the orchestra is

\text{(A)}\ 10 \qquad \text{(B)}\ 20 \qquad \text{(C)}\ 30 \qquad \text{(D)}\ 50 \qquad \text{(E)}\ 70

Solution

There are 100+80-60=120 females in either band or orchestra, so there are 230-120=110 males in either band or orchestra. Suppose x males are in both band and orchestra. By PIE, 80+100-x=110\Rightarrow x=70. Thus, the number of males in band but not orchestra is 80-70=10\rightarrow \boxed{\text{A}}.

See Also

1991 AJHSME (ProblemsResources)
Preceded by
Problem 22
Followed by
Problem 24
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