The way I do it, when I do vertical division, is to add a decimal mark and zeroes if needed) in the quotient, until the dividend is greater than the divisor.
For example, 5.3/70 would start as:
5.3|70
....|....
I would start by setting the problem on paper with the divisor (70) on the left, the dividend (53) on the right, with a line over as a place for the quotient (answer), like so:
Rich (BB code):
-------
70 |53.0
First we ask "how many times does 70 go evenly into 53? As the answer is zero we write that down in the units position.
Rich (BB code):
0
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70 |53.0
We are out of integers and now must work with decimals, so in the quotient area add a decimal place. In the dividend area add a zero so we can work down 10 times the precision of the number we have:
Rich (BB code):
0.
-------
70 |53 0
Our question is now how many times does 70 go into 530, which is 7. Write the 7 down in the quotient, and write the product of 7*70 (= 490) below the dividend, and subtract:
Rich (BB code):
0.7
-------
70 |53 0
-49 0
-------
4 0
As we still have a remainder we again tack on the zero to the remainder and see how many times does 70 go into 400, which is 5, and we mark down 5 times 70 below the remainder and again subtract: