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OK, so WHY does this work?

Let's write the last problem as a fraction:

6.85 divided by .5 is the same as 6.85 / .5

Can we multiply this fraction by 1 and not change its value?  Yep!

How about if we multiply by a magic 1?

10 / 10

YEP!

6.85 / .5  x  10 / 10 = 68.5 / 5 which gives us 68.5 divided by 5

So, just moving both decimals to the right

moving the decimals points one place to the right on the problem 6.85 divided by .5

is the same as multiplying by a magic 1!

Here's another one:

Divide 7.5 by .25

Set it up...

moving the decimal points over two places which changes the problem 7.5 divided by .25 into the new problem 750 divided by 25

Hey, there aren't even any decimals left in this one!

Go for it:

long division work for the problem 750 divided by 25...  So, 7.5 divided by .25 is 30

decimals10-09.gif

Always remember what division means and think about your answers!

This problem means:

How many .25's are there in 7.5?
There are 30.

Think about it!  Does this answer make sense?