Question

Question 6

In the following question, out of the four options, only one is correct. Write the correct answer:

The value of ${\left(\frac{2}{5}\right)}^{-2}$ is
(a) $\frac{4}{5}$
(b) $\frac{4}{25}$
(c) $\frac{25}{4}$
(d) $\frac{5}{2}$

Answer 1

Using law of exponents, $a^{-m}=\frac{1}{a^m}$

$\therefore {\left(\frac{2}{5}\right)}^{-2}=\frac{1}{{\left(\frac{2}{5}\right)}^2}$

$={\left(\frac{5}{2}\right)}^2$

$=\frac{25}{4}$