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1987 AJHSME Problems/Problem 16

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Problem

Joyce made 12 of her first 30 shots in the first three games of this basketball game, so her seasonal shooting average was 40\%. In her next game, she took 10 shots and raised her seasonal shooting average to 50\%. How many of these 10 shots did she make?

\text{(A)}\ 2 \qquad \text{(B)}\ 3 \qquad \text{(C)}\ 5 \qquad \text{(D)}\ 6 \qquad \text{(E)}\ 8

Solution

After the fourth game, she took 40 shots, 50\% of which she made, so she made 40\times .5=20 shots. Twelve of them were made in the first three games, so in the last game she made 20-12=8 shots.

\boxed{\text{E}}

See Also

1987 AJHSME (ProblemsResources)
Preceded by
Problem 15
Followed by
Problem 17
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
Want to learn how to tackle those tough MATHCOUNTS and AMC counting and probability problems? Check out Art of Problem Solving's Introduction to Counting & Probability by David Patrick.
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