# How do you write the answer in scientific notation given (9.9times10^9)/(1.5times10^8)?

Mar 21, 2017

$6.6 \times 10$

#### Explanation:

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Example demonstrating a principle using 'easy' numbers

Suppose we had ${5}^{3} / {5}^{2}$

This is the same as:$\text{ } \frac{5 \times 5 \times 5}{5 \times 5}$

Split this so that we have:$\text{ } 5 \times \frac{5}{5} \times \frac{5}{5}$

But $\frac{5}{5} = 1$

$5 \times 1 \times 1 = 5$

Another way of doing this is:$\text{ } {5}^{3} / {5}^{2} = {5}^{3 - 2} = {5}^{1} = 5$

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Write as:$\text{ } \frac{9.9}{1.5} \times {10}^{9} / {10}^{8}$

Using the method as in the example write as:

$\frac{9.9}{1.5} \times {10}^{9 - 8}$

$\frac{9.9}{1.5} \times {10}^{1}$

but 9.9-:1.5=6.6# giving:

$6.6 \times 10$

We have a whole number to the left of the equals that is less than 10 so this is the finished answer.