What is the value of (2^0-1+5^2+0)^-1× 5?

2015 AMC 12A Problem 1

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What is the value of

(2^0-1+5^2+0)^{-1}\times 5?

-125

-120

\dfrac{1}{5}

\dfrac{5}{24}

25

Evaluate inside the parentheses first, using

2^0=1

-1

exponent means take the reciprocal before multiplying by

5

Inside the parentheses,

\begin{aligned} &2^0-1+5^2+0 \\ &\quad = 1-1+25+0 = 25. \end{aligned}

Then

(25)^{-1}\times 5 = \dfrac{5}{25} = \dfrac{1}{5}.

Thus, the correct answer is C.