Step by step
The question
Question: work out 5.4 × 10⁸ divided by 1.8 × 10⁻³.
5.4 × 1081.8 × 10−3
1 Group the parts
We divide the numbers, and we divide the powers of 10.
= 5.41.8 × 10810−3
2 Work out each part
5.4 divided by 1.8 is 3.
5.4 ÷ 1.8 = 3
We write 3 for the numbers.
= 3 × 10810−3
The rule: when we divide powers of the same number, here 10, we take away the powers.
8 minus −3: taking away a minus is adding.
That is 11.
10810−3 = 108 − (−3)
= 1011
So the answer is 3 × 10¹¹.
= 3 × 1011
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 1011
Let's look back.
First: group the parts.
Then: work out each part.
Last: check.
Answer
= 3 × 1011