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1986 AJHSME Problems/Problem 11

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Problem

If \text{A}*\text{B} means \frac{\text{A}+\text{B}}{2}, then (3*5)*8 is

\text{(A)}\ 6 \qquad \text{(B)}\ 8 \qquad \text{(C)}\ 12 \qquad \text{(D)}\ 16\qquad \text{(E)}\ 30

Solution

We just plug in and evaluate: \begin{align*}(3*5)*8 &= \left( \frac{3+5}{2}\right) *8 \\&= 4*8 \\&= \frac{4+8}{2} \\&= 6 \\\end{align*}

\boxed{\text{A}}

See Also

1986 AJHSME (Problems • Resources)
Preceded by
Problem 10 		Followed by
Problem 12
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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