Step by step
The question
Question: work out 9 × 10⁷ divided by 3 × 10².
9 × 1073 × 102
1 Group the parts
We divide the numbers, and we divide the powers of 10.
= 93 × 107102
2 Work out each part
9 divided by 3 is 3.
9 ÷ 3 = 3
We write 3 for the numbers.
= 3 × 107102
The rule: same base, divide, take away the powers.
7 minus 2 is 5.
107102 = 107 − 2 = 105
So the answer is 3 × 10⁵.
= 3 × 105
3 Check
Let's check the answer is in scientific notation.
3 is from 1 to under 10, and it is times a power of 10.
Yes!
3 is from 1 to under 10, times 105
Let's look back.
First: group the parts.
Then: work out each part.
Last: check.
Answer
= 3 × 105