Negative division

Thread Starter

Lightfire

Joined Oct 5, 2010
690
Hello,

I just want to ask how to divide this;

53 divided by 70.:)Using a paper and pen. I can only divide if it is;
70 divided by 53.

Thanks!
 

Georacer

Joined Nov 25, 2009
5,182
Try this:
53/70=
(530/70)/10

Do you know how to do this one?

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
....|....

And I would re-work it as:
530|70
----|0.0

and continue with the division normally.
 

ErnieM

Joined Apr 24, 2011
8,377
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
   -------
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:

Rich (BB code):
     0.75
   -------
70 |53.0
   -49 0
   -------
     4 00
    -3 50
   -------
       50
Those are the basic steps. You keep repeating until either the remainder is zero, or you have sufficient precision in the quotient.
 
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