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#1 2006-10-05 04:33:21

cambridge
Member
Registered: 2006-09-06
Posts: 3

Helpppppppppppppppp with decimals

dizzy i need help with decimal points can anyone help me plz (everythin) dunno

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#2 2006-10-05 05:24:23

espeon
Real Member
Registered: 2006-02-05
Posts: 2,586

Re: Helpppppppppppppppp with decimals

um if youre adding or subtracting or using a deciaml point in the colunm method then alwaysmake sure ur putting the decimal point at the right place. like this...

  65.9                   
+73.3
_______
139.2

and not like this...

  6.95
+733.
_______
  (cant be done)


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#3 2006-10-05 07:30:53

cambridge
Member
Registered: 2006-09-06
Posts: 3

Re: Helpppppppppppppppp with decimals

thanx for helping me! i understand now!

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#4 2006-10-05 07:37:15

Devantè
Real Member
Registered: 2006-07-14
Posts: 6,400

Re: Helpppppppppppppppp with decimals

Also, when you get something hard, like 2.2272 x 3.1286, use another strategy.

2.2272 x 3.1286 = (22272 x 31286)/1000

I always try to get rid of the decimal place before doing things like that. If I don't have time, though, I just do the bare sum itself, on its own.

Last edited by Devanté (2006-10-05 07:37:35)

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#5 2006-10-05 07:53:31

espeon
Real Member
Registered: 2006-02-05
Posts: 2,586

Re: Helpppppppppppppppp with decimals

urrrrrrrrrr i just do it with the decimal points. because with my useless memory ill forget aboutt he pint lol


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#6 2006-10-05 08:12:58

polylog
Member
Registered: 2006-09-28
Posts: 162

Re: Helpppppppppppppppp with decimals

@ cambridge:

as espeon said, just remember to *align the decimal points* for addition and subtraction, make sure that you have them in the same spot in the top and bottom number.
Also remember that you can write as many 0s as you want after the final digit behind the decimal point: for example 1.2 = 1.20 = 1.200 = 1.2000 ...

so say you need to add 1.23 and 2.23432

write it like this for the addition:

2.23432
1.23000
---------

so that the decimals align!

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#7 2006-10-05 08:59:17

Patrick
Real Member
Registered: 2006-02-24
Posts: 1,005

Re: Helpppppppppppppppp with decimals

For more information, look at some of all the great articles we have here on mathsisfun.com about decimals:
http://www.mathsisfun.com/decimals-menu.html


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#8 2006-10-05 10:06:38

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

Re: Helpppppppppppppppp with decimals

Devanté wrote:

2.2272 x 3.1286 = (22272 x 31286)/1000

1) Moving 4 decimal places means you need /10000.
2) You've done it twice, so you actually need /10000².


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#9 2006-10-05 17:52:37

Devantè
Real Member
Registered: 2006-07-14
Posts: 6,400

Re: Helpppppppppppppppp with decimals

Mjeh. It was the night.

But thanks for pointing that out. I am getting dumber? >_>

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