Question

Mark the correct alternative in each of the following:

$\frac{-7}{13}-\left(\frac{-8}{15}\right)=$

(a) $-\frac{239}{195}$ (b) $\frac{29}{195}$ (c) $\frac{-29}{195}$ (d) None of these

Answer 1

$$\begin{gathered} \frac{-7}{13}-\left(\frac{-8}{15}\right) \\ =\frac{-7}{13}+\frac{8}{15}\left[-\left(\frac{-8}{15}\right)=\frac{8}{15}\right] \\ =\frac{-7\times 15+8\times 13}{195}\left(\mathrm{LCM}\mathrm{of}13\mathrm{and}15=195\right) \\ =\frac{-105+104}{195} \\ =\frac{-1}{195} \end{gathered}$$

Hence, the correct answer is option (d).