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#1 2013-09-07 05:50:21

fergul
Novice

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Division without calculator

What am I doing wrong with this division
561/15

My ans 37.6? I know this is incorrect on calculator it is 37.4

My working out:

56/15 is 3 with 11 remaining

111/15 is 7 with 6 remaining.

I like doing division in standard manner and layout rather than rounding up or using factors etc.

#2 2013-09-07 05:54:57

bobbym
Administrator

Online

Re: Division without calculator

Hi;

Just continue the process. 60 / 15  is 4.

Remember to put the 0 after the decimal point when you start. 561 is written as 561.0 so when you get that last carry you can continue past the decimal point.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#3 2013-09-07 06:44:40

fergul
Novice

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Re: Division without calculator

I know this may sound stupid but how do you know to add 0 and keep dividing? When you get 4, how do you know that is the end? Why don't you add 0 to 40 and divide again by 15?

#4 2013-09-07 06:47:43

bobbym
Administrator

Online

Re: Division without calculator

You just keep adding it to the next digit like you were doing before the decimal. If you have a remainder of 5 and the next digit is 0 then it becomes a 50. This can happen before the decimal too.

Of course 561 is the same as 561.0 or 561.00 or 561.000 etc.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#5 2013-09-07 07:10:08

fergul
Novice

Offline

Re: Division without calculator

Thanks, I think I get it now.

#6 2013-09-07 07:16:13

bobbym
Administrator

Online

Re: Division without calculator

That is very good and welcome to the forum. try a few more and come back with any questions. Good luck.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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