# How do you write 24.5 times 10^-5 in scientific notation?

Feb 19, 2016

$2.45 \times {10}^{-} 4$

#### Explanation:

A number in scientific notation is written in the form

$a \times {10}^{n} \text{ where 1≤ a < 10 and n is an integer }$

we are also going to make use of ${a}^{m} \times {a}^{n} = {a}^{m + n}$

first write 24.5 in scientific notation
require 24.5 to be written as a number between 1 and 10

hence 24.5 = 2.45 , but requires to be multiplied by 10 to retain it's original value.

$24.5 = 2.45 \times 10 = 2.45 \times {10}^{1}$

$\Rightarrow 24.5 \times {10}^{-} 5 = 2.45 \times {10}^{1} \times {10}^{-} 5 = 2.45 \times {10}^{-} 4$