Why do you move decimal points over when you divide?

Question

I was just thinking how when I was in school, teachers always said that you need to move the decimal point over when you divide. Why do we need to do it and how come it works?

Answer 1

You need to do that because if you do not move the decimal point, the answer would most likely be off. It's easier to do it before yo divide then after you find the solution.

Answer 2

It is just a simple way to divide by a multiple of 10. You do not necessarily have to just move the decimal place, you could still divide.

Answer 3

The reason is usually because it's proper form to have fractions expressed as integers rather than decimals. For instance, take this example:

1.2 / 2.2

Let's move the decimal point over; once for each of the top and bottom.

12 / 22

Note that they are now integers. We can now reduce them like integers, to get

6/11

Sometimes, it's better to leave fractions as fractions instead of dividing them out and reducing them as decimals, because decimals have this tendency to be approximations rather than exact values.

Take 6.6 / 9.9

If we move the decimal point over, it becomes

66/99

Which we can reduce to

2/3

It is preferable to have EVERYTHING expressed as a fraction of integers.

Answer 4

this is so you are not confused with where to put the decimal after dividing.