Question

Mark (✓) against the correct answer
$\left({\frac{-2}{3}}^{10}\right)÷{\left(\frac{-2}{3}\right)}^8=?$

(a) $\frac{4}{9}$
(b) $\frac{-4}{9}$
(c) ${\left(\frac{-2}{3}\right)}^{18}$
(d) none of these

Answer 1

(a) $\frac{4}{9}$


${\left(\frac{-2}{3}\right)}^{10}÷{\left(\frac{-2}{3}\right)}^8$ = ${\left(\frac{-2}{3}\right)}^{10-8}$ $\left[s\mathrm{ince}{a}^m÷a^n=a^{m-n}\right]$
= ${\left(\frac{-2}{3}\right)}^2$
= $\frac{{\left(-2\right)}^2}{3^2}=\frac{4}{9}$