2015 AMC 10A Problems/Problem 1

The following problem is from both the 2015 AMC 12A #1 and 2015 AMC 10A #1, so both problems redirect to this page.

Problem

What is the value of $(2^0-1+5^2-0)^{-1}\times5?$

$\textbf{(A)}\ -125\qquad\textbf{(B)}\ -120\qquad\textbf{(C)}\ \frac{1}{5}\qquad\textbf{(D)}}\ \frac{5}{24}\qquad\textbf{(E)}\ 25$ (Error compiling LaTeX. Unknown error_msg)

Solution

$(2^0-1+5^2-0)^{-1}\times5$ $=(1-1+\frac{1}{25}-0)^{-1}\times5$ $={\frac{1}{25}}^{-1}\times5$ $=-25\times5$ $=-125\implies{\boxed{\textbf{(C)}\ -5}}$

2015 AMC 10A (Problems • Answer Key • Resources)
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All AMC 10 Problems and Solutions

2015 AMC 12A (Problems • Answer Key • Resources)
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All AMC 12 Problems and Solutions

The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions.

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2015 AMC 10A Problems/Problem 1

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