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Teesha Block
 
 

How do I simplify the following?

by Teesha Block Thu Mar 13, 2008 10:46 pm

I got to this point on a problem and am wondering if there is a simple way to simply it. Please help. Thanks!!!

207 / 1.15
RonPurewal
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Re: How do I simplify the following?

by RonPurewal Fri Mar 14, 2008 4:48 am

Teesha Block Wrote:I got to this point on a problem and am wondering if there is a simple way to simply it. Please help. Thanks!!!

207 / 1.15


if you have a decimal in the denominator of a fraction, do one of the following (they're equivalent, so do whichever you're more comfortable with):
1) multiply by a power of 10 big enough to clear the decimal;
2) make the decimal points on the top and bottom 'dance' the same number of places in parallel. (if there's no decimal point, as in the numerator of your fraction, then put one at the end.)

if you like #1 better, then multiply both sides of the fraction by 100 (because the bottom has hundredths in it). if you like #2 better, then make both decimal places 'dance' two steps to the right.

in either case, you'll get 20700 / 115, whereupon long division yields 180.
rohit801
 
 

by rohit801 Tue Mar 18, 2008 2:32 pm

i had a suggestion/thought on divisions such as 207/1.15. What Ron said, makes perfect sense.
i have found the following useful also and wanted to share my thoughts:

207/1.15 = 2070/11.5. now when i notice a "half" such as 11.5, i like ro replace that with the proper fraction, 23/2, in this case.
so, 2070 * 2/23. then carry out the calculation.

Reason: if you make 1.15 -> 115, you have 20700/115. now you have to start reducing the fraction anyways. so, by making 1.15->11.5 and taking it as 23/2, i already have reduced numbers to work with instead of getting to 115 and then reducing it down.

JUST a thought/preference.
would love Ron, the expert, to comment on this.

thanks
StaceyKoprince
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by StaceyKoprince Thu Mar 27, 2008 2:17 am

rohit, that's a great tip. For anyone considering this, just make sure that this won't introduce a chance for you to make a careless error - if you feel entirely comfortable thinking this way, then do it, but if you may make a mistake with it, then don't.

The other thing you can do (rather than long division) is just simplify, simplify, simplify. eg, the top and bottom are both divisible by 5, so you might start there.
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