## Prealgebra (7th Edition)

a. $\frac{16}{625}$ b. $\frac{1}{16}$
a. $(\frac{2}{5})^{4}$ $=\frac{2^{4}}{5^{4}}$ $=\frac{2\times2\times2\times2}{5\times5\times5\times5}$ $=\frac{4\times2\times2}{25\times5\times5}$ $=\frac{8\times2}{125\times5}$ $=\frac{16}{625}$ b. $(-\frac{1}{4})^{2}$ $=\frac{1^{2}}{4^{2}}$ $=\frac{1\times1}{4\times4}$ $=\frac{1}{16}$