Help Conversion help

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Need to convert circumference to diameter for two circles. Easy you say? Nah, I'm shocking at that sort of math and the conversion calculators I've found will only convert whole numbers into decimals, I need them in eighths.

First circle 4 1/8"

Second 7 1/8"

Help??
 

Raven

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Easy, first convert into decimal

Then divide it by 3.14 (pi)

Then convert back to imperial


4 1/8 = 104.775mm
104.775mm / 3.14 = 33.37mm
33.37mm = 1.31 inches... or 1 and 3/10 (but not precisely)

Goes to show why Imperial sucks at small numbers.
 

Zarjazz

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No conversion necessary. Just divide by PI.

4.125 / 3.14 = 1.313 ~ 1 5/16" diameter (2.5 eighths - Glad I never had to use the imperial system, it's fucking awful.)

7.125 / 3.14 = 2.268 ~ 2 2/8" diameter​
 

Raven

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Imperial is fine for measuring large distances, drinks servings and cooking!

What sort of a cunt walks into a pub and asks the barman for 568.2ml of beer?
 

Zarjazz

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You mean you don't?? You can't be too careful with those lax bar staff giving short measures.
 

gohan

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No conversion necessary. Just divide by PI.

4.125 / 3.14 = 1.313 ~ 1 5/16" diameter (2.5 eighths - Glad I never had to use the imperial system, it's fucking awful.)

7.125 / 3.14 = 2.268 ~ 2 2/8" diameter​
I guess the conversion is to save on mistakes. For example if it was 2.25 you have to remember that's 2 foot 3 inches not 2 foot 2.5 inches. Easy enough if you've worked in both but if you rarely use imperial it's easy to cock up
 

caLLous

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You wouldn't use a decimal point there like that though. If it's 2.25 that will always mean 2 feet and 0.25 of a foot. I mean, the decimal part would always be tenths or hundredths or thousandths of whatever unit the integer is.
 
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gohan

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No I know, it would be 2' 3" but it's still an easy mistake to make when you've been brought up on multiples of ten :p
 

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