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chebytrk
12-05-2011, 09:36 AM
I know this is kinda...... dumb, but math was not my favorite subject. So how or what is the formula to figure out that .750 is 3/4 or .625 is 5/8? I know the CW does this automatically, but I'd like to know the formula on how this is done. Thnx

dbfletcher
12-05-2011, 09:48 AM
That is just long division. here is a site that will help refresh your memory. let me know if you are still confused. (you can walk thru each step so you see how it is done)

http://www.mathsonline.org/pages/longdiv.html (make sure you specify decimal division or it will just give you remainders... not very helpful for your question)

edit: After reading Jaustins post, I realize you may have wanted to go the other way. Well.. now you have links that you can use to go in either direction!

jaustin
12-05-2011, 09:49 AM
How to do it formula

http://www.mathsisfun.com/converting-decimals-fractions.html (http://www.mathsisfun.com/converting-decimals-fractions.html)

Or like I do print out a fraction to decimal cheat sheet.
http://summitupperschool.org/lgarrett/files/2011/04/fraction_decimal.gif

AskBud
12-05-2011, 10:16 AM
I know this is kinda...... dumb, but math was not my favorite subject. So how or what is the formula to figure out that .750 is 3/4 or .625 is 5/8? I know the CW does this automatically, but I'd like to know the formula on how this is done. ThnxThree divided by four equals .750.

The reverse is a bit harder for me to explain! We'll use your example of .625.
625 parts of 1000 or 1000 minus 625 leaves 375. Now let's see what small number I can reduce 625 by! Since both numbers end in 5, I'll start with (625/5=125). Next I'll take the 125 and see if it will work well with 375. YES, (375/125=3). This reduction process shows me I have 8 total parts (5+3=8 ), therefore, .625 is 5/8!
AskBud

Oak Tech
12-05-2011, 12:14 PM
Jerry B.

Attached is a chart that I developed for my shop to reduce fractions to their lowest form. It will also convert decimal to fraction or fraction to decimal.

The decimals are in parenthases.

Hope this helps,

Bob

bergerud
12-05-2011, 12:23 PM
To convert from decimals to a fraction in 64ths, just try multiplying by 8, 16, 32, or 64. The first time you get a whole number, you have got it. For example 0.3125 X 8=2.5, nope, 0.3125 X 16=5, ok so it is 5/16. If you never get a whole number then it is not a fraction in 64ths.

Jeff_Birt
12-05-2011, 12:29 PM
To convert from decimals to a fraction in 64ths, just try multiplying by 8, 16, 32, or 64. The first time you get a whole number, you have got it. For example 0.3125 X 8=2.5, nope, 0.3125 X 16=5, ok so it is 5/16. If you never get a whole number then it is not a fraction in 64ths

That is a very clever and quick method!

bayea
12-05-2011, 01:22 PM
divide the numerator by the denominator . . . 3 divided by 4 = .75

ktjwilliams
12-07-2011, 11:18 PM
WOW !!!! All these terrible memories just came rushing back to me,, of the nuns beating me,, with those standard issue steel rulers they all carried,, telling me that I'll learn math or else !!!!