#### Answer

=$-\frac{7}{40}$

#### Work Step by Step

$(-\frac{1}{2})(\frac{2}{5})(\frac{7}{8})\longrightarrow$ Solve left to right. To multiply fractions, multiply numerator by numerator and denominator by denominator. The first product is negative because the two factors have opposite signs.
=$(-\frac{2}{10})(\frac{7}{8})\longrightarrow$ Multiply, The product is negative because the two factors have opposite signs.
=$-\frac{14}{80}\longrightarrow$ Reduce using the greatest common factor, 2.
=$-\frac{14\div2}{80\div2}\longrightarrow$ Simplify.
=$-\frac{7}{40}$