Question

Mark the correct alternative in the following question:

$$\begin{gathered} {\left(3^{-1}\times 5^{-1}\right)}^{-1}= \\ \left(\mathrm{a}\right)\frac{1}{15}\left(\mathrm{b}\right)-\frac{1}{15}\left(\mathrm{c}\right)15\left(\mathrm{d}\right)-15 \end{gathered}$$

Answer 1

$$\begin{gathered} {\left(3^{-1}\times 5^{-1}\right)}^{-1} \\ ={\left(\frac{1}{3}\times \frac{1}{5}\right)}^{-1}\left(\mathrm{As},x^{-1}=\frac{1}{x}\right) \\ ={\left(\frac{1}{15}\right)}^{-1} \\ =\frac{15}{1}\left(\mathrm{As},x^{-1}=\frac{1}{x}\right) \\ =15 \end{gathered}$$

Hence, the correct alternative is option (c).