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Unregistered
05-09-2009, 11:36 AM
When I type in 16mm and select inch the conversion is in decimals of an inch.
How do I use OnlineConversion to convert mm to fractions of an inch?
Thanks.

create_community
05-09-2009, 01:49 PM
Hi, If I understand correctly, you wish to convert 16mm to inches, expressed as a fraction of an inch using proper fractions, not decimals. The reason your teacher says to express your answer as a fraction is so you will work the problem by hand, not use a calculator!

You need to know 4 things to solve any problem like this:
First, what a millimeter is, expressed as a fraction of a meter. It is 1/1000 of a meter (milli means a thousandth).

Second, how to do the arithmetic involved in simple fractions. This means you need to know your times tables. They are easy to learn in about 15 minutes, and we can help with that if you need to learn it.

Third, you need to know just one measurement that is exactly equivalent between a metric distance unit of measure (like a meter, or centimeter, or millimeter) and its equivalent old-fashioned unit of measure. "Equivalent" means a different name for the exact same thing. This equivalence, or conversion factor, is something to memorize once and then use for the rest of your joyful life! The easiest one is this: 1 inch=2.54 cm.
One inch equals 2.54 centimeters.

And fourth: you need to know how to go back and forth between a decimal (which often is not an exact number) and a fraction (which is perfectly precise). Here is an example you already know: Change 1/2 into a decimal.
It looks like "one half" because that's what we call 1/2. But in math this (1/2) thing REALLY is: one divided by two. OK Divide one by 2. You also could write it this way: "2 goes into 1", etc. The answer is .5 If you need to learn how to do that division, let us know. We can teach you. It's fun!

OK now we get to play with all 4 pieces. Ready? :) ;) See my next post, and reply telling me how you're doing so far. It's gong to take us 3 posts to solve your problem, and make you forever able to solve all kinds of problems in math, chemistry, physics, money, and compute your gas mileage too!

:)

Robert Fogt
05-09-2009, 04:24 PM
If you have decimal inches you can convert to fractions here:
http://www.onlineconversion.com/fractions.php

Keep in mind it converts to and from decimal and fractions, it doesnt change the units. First you would need to convert millimeters to inches then use the above to convert to fractions.

06-10-2009, 02:45 AM
hey guys... i need some help... i wanna know how to convert a fraction, such as 23/64, into millimeters without the use of a chart which is not often availiable all the time.. i want to know how to do the working out in my head... converting fractions to millimeters and vise versa. thanks... cheers

JohnS
06-10-2009, 07:02 AM
hey guys... i need some help... i wanna know how to convert a fraction, such as 23/64, into millimeters without the use of a chart which is not often availiable all the time.. i want to know how to do the working out in my head... converting fractions to millimeters and vise versa. thanks... cheers

Your calculator will show a fraction as decimal inches:
23/64 = 0.359375"

There are exactly 25.4 mm in 1", so multiply the above by 25.4:
9.128125 mm.

You have to decide where to round off, but if you are measuring to nearest 64ths, I would suggest the nearest 0.1 mm, ie 9.1 mm. Anything beyond that is "decimal dust." (1/64 is about 0.4 mm, 1/2 that is 0.2 mm, so 0.1 mm has slightly more resolution than mesuring to nearest 64th, in fact, it is about equivalent to measuring to the nearest 128th)

You can do this all in one operation:
25.4*23/64

Unregistered
02-01-2012, 07:58 PM
i need to convert 15/16 to64ths

Unregistered
02-08-2012, 12:38 AM
15/16 = 30/64 (multiply by 4 :-))

JohnS
02-08-2012, 03:26 AM
15/16 = 30/64 (multiply by 4 :-))

15 x 4 = 60 so 60/64.

Johnny morgan
09-08-2012, 06:55 AM
hey guys... i need some help... i wanna know how to convert a fraction, such as 23/64, into millimeters without the use of a chart which is not often availiable all the time.. i want to know how to do the working out in my head... converting fractions to millimeters and vise versa. thanks... cheers
I want tobe able to convert the smallest millimeter to fraction

JohnS
09-08-2012, 11:21 AM
I want tobe able to convert the smallest millimeter to fraction

1 mm equals 5/127 of an inch exactly. Unfortunately carpenters don't use 127ths much.

Divide by 25.4 mm/in to convert to decimal inches, then convert the fractional part to a common fraction. If you want 64ths, multiply by 64 then round result to integer. It is not exact.