Question:
Mark (✓) against the correct answer
The product of two numbers is $\frac{-1}{4}$. If one of them is $\frac{-3}{10}$, then the other is
(a) $\frac{5}{6}$
(b) $\frac{-5}{6}$
(c) $\frac{4}{3}$
(d) $\frac{-8}{5}$
Solution:
(a) $\frac{5}{6}$
Let the required number be
Now,
$\frac{-3}{10} \times x=\frac{-1}{4}$
$\Rightarrow x=\frac{-1}{4} \div\left(\frac{-3}{10}\right)$
$\Rightarrow x=\frac{-1}{4} \times \frac{10}{-3}$
$\Rightarrow x=\frac{10}{12}=\frac{5}{6}$