# How do you simplify (4 times 10^8)^-2 and write the answer in scientific notation?

Jan 27, 2016

$6.25 \times {10}^{-} 18$

#### Explanation:

The expression is equals to:

${\left(4 \times {10}^{8}\right)}^{- 2} = \frac{1}{4 \times {10}^{8}} ^ 2 =$

$= \frac{1}{4} ^ 2 \times \frac{1}{{10}^{16}} =$

$= \frac{1}{16} \times {10}^{- 16} = 0.0625 \times {10}^{- 16}$

$0.0625 \times {10}^{- 16} = 6.25 \times {10}^{- 18}$