Dividing by ten
When we divide a number ending in zero by 10, we can remove one zero from the end of the number.
For example:
Both 50 and 10 end in one zero. We can remove one zero from both numbers:
The same rule works with larger numbers:
We remove one zero from both numbers:
Dividing by whole tens
Whole tens are numbers such as 10, 20, 30, 40, 50 and so on. They always end in one zero.
When both the dividend and the divisor end in zero, we can remove the same number of ending zeros from both numbers. Then we divide the remaining numbers.
For example:
Both numbers end in one zero, so remove one zero from each:
Therefore:
The same method works with other whole tens:
Both numbers end in one zero, so remove one zero from each to get $360 ÷ 6$:
Therefore:
Dividing numbers that end in zero
When the dividend ends in zero, we can sometimes temporarily remove the zero, divide the remaining number, and then put the zero back at the end of the result.
For example:
First, ignore the zero at the end of 270:
The original number 270 had one zero at the end, so we put this zero back after 9:
Therefore:
This method works because:
So:
The same idea works with more zeros.
For example:
Temporarily remove the two ending zeros:
Then put the two zeros back:
Therefore:
