18

Part of 1956 AMC 12/AHSME

Problems(1)

Source:

If 10^{2y} \equal{} 25, then 10^{ \minus{} y} equals: (A)\ \minus{} \frac {1}{5} \qquad(B)\ \frac {1}{625} \qquad(C)\ \frac {1}{50} \qquad(D)\ \frac {1}{25} \qquad(E)\ \frac {1}{5}