The expression 1^4y-15^-1+3^-1 is equal to:

1962 AMC 12 Problem 1

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The expression

\dfrac{1^{4y-1}}{5^{-1}+3^{-1}}

is equal to:

\dfrac{4y-1}{8}

8

\dfrac{15}{2}

\dfrac{15}{8}

\dfrac18

First simplify the power in the numerator

Rewrite each negative first power as a reciprocal

The numerator is

1,

while

5^{-1}+3^{-1}=\frac15+\frac13=\frac8{15}.

Therefore the expression equals

\frac{1}{\frac{8}{15}}=\frac{15}{8}.

Thus, the correct answer is D.