# How do you multiply (2.4 * 10^-5)(4 * 10^-4)?

Mar 14, 2018

See a solution process below:

#### Explanation:

First, rewrite this expression as:

$\left(2.4 \cdot 4\right) \cdot \left({10}^{-} 5 \cdot {10}^{-} 4\right) \implies$

$9.6 \cdot \left({10}^{-} 5 \cdot {10}^{-} 4\right)$

Now, use this rule of exponents to multiply the 10s terms:

${x}^{\textcolor{red}{a}} \times {x}^{\textcolor{b l u e}{b}} = {x}^{\textcolor{red}{a} + \textcolor{b l u e}{b}}$

$9.6 \cdot \left({10}^{\textcolor{red}{- 5}} \cdot {10}^{\textcolor{b l u e}{- 4}}\right) \implies$

$9.6 \cdot {10}^{\textcolor{red}{- 5} + \textcolor{b l u e}{- 4}} \implies$

$9.6 \cdot {10}^{-} 9$