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1989 AJHSME Problems/Problem 7

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Problem

If the value of 20 quarters and 10 dimes equals the value of 10 quarters and n dimes, then n=

\text{(A)}\ 10 \qquad \text{(B)}\ 20 \qquad \text{(C)}\ 30 \qquad \text{(D)}\ 35 \qquad \text{(E)}\ 45

Solution

We have \begin{align*}20(25)+10(10) &= 10(25)+n(10) \\600 &= 250+10n \\35 &= n \rightarrow \boxed{\text{D}}\end{align*}

See Also

1989 AJHSME (Problems • Resources)
Preceded by
Problem 6 		Followed by
Problem 8
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
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