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2000 AMC 10 Problems/Problem 3

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Problem

Each day, Jenny ate 20\% of the jellybeans that were in her jar at the beginning of that day. At the end of the second day, 32 remained. How many jellybeans were in the jar originally?

\mathrm{(A)}\ 40 \qquad\mathrm{(B)}\ 50 \qquad\mathrm{(C)}\ 55 \qquad\mathrm{(D)}\ 60 \qquad\mathrm{(E)}\ 75

Solution

x(.8)(.8)=32

x(.64)=32

x \cdot \frac{32}{50}=32

x=50

\boxed{\text{B}}

See Also

2000 AMC 10 (ProblemsResources)
Preceded by
Problem 2
Followed by
Problem 4
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