# How do you write 0.721 in scientific notation?

Aug 18, 2016

$0.721 = 7.21 \times {10}^{-} 1$

#### Explanation:

In scientific notation, there must be only 1 digit in front of the decimal point. The size of the number is given as a power of 10

$0.721 = 7.21 \times {10}^{-} 1$

Consider the following:

$0.721 = \frac{721}{1000} = \frac{72.1}{100} = \frac{7.21}{10}$

Using laws of indices, we can write

$\frac{7.21}{10} = 7.21 \times {10}^{- 1}$