# How do you work out (3.2times10^5)times(4.5times10^4)?

$= \left(3.2 \times 4.5\right) \times \left({10}^{5} \times {10}^{4}\right)$
$= 14.4 \times {10}^{5 + 4} = 14.4 \times {10}^{9}$
$= 1.44 \times 10 \times {10}^{9} = 1.44 \times {10}^{10}$