Question

Tick (✓) the correct answer
$\left\{{\left(\frac{1}{3}\right)}^{-3}-{\left(\frac{1}{2}\right)}^{-3}\right\}÷{\left(\frac{1}{4}\right)}^{-3}=?$
(a) $\frac{19}{64}$
(b) $\frac{27}{16}$
(c) $\frac{64}{19}$
(d) $\frac{16}{25}$

Answer 1

(a) $\frac{19}{64}$

$$\begin{gathered} \left\{{\left(\frac{1}{3}\right)}^{-3}-{\left(\frac{1}{2}\right)}^{-3}\right\}÷{\left(\frac{1}{4}\right)}^{-3} \\ =\left\{3^3-2^3\right\}÷4^3 \\ =\left\{27-8\right\}÷64 \\ =19÷64 \\ =\frac{19}{64} \end{gathered}$$