----- Original Message ----- From: "millitesla" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Wednesday, 2001-02-14 12:43 Subject: Re: decimals not fractions? [Yahoo! Clubs: Metric America] > Neil, > > Fractions should be avoided when using metric. In reality fractions are not real numbers, they are a form of incomplete division. Fractions developed at a time when people could not do math. Dividing 1 by 4 to get 0.25 was something only the educated could do. > > Think about it!! How many fraction variations are used in imperial? How many people use 1/3 inch? Fractions are done in halves, quarters, eighths, etc. This is because even the ignorant can break something in half repeatedly. Yet, even the masses despite years of education today can not function in a fractional world. Their use of fractions goes no farther than 16-ths and only to a point of expressing the fraction, not manipulating it mathematically. Its one thing to ask for a quarter pound of something and another thing to add a quarter to an eight and get a result. > > Don't try to accommodate ignorant practices!! This is called "dumbing down". Ignorance is not bliss. > > A number like 3.333 brings up another issue. How many places do you need past the decimal point? Because the millimetre is small, it is really impractible in most applications to have more than one decimal place. The ignorant whether dividing out fractions with a calculator or converting from imperial to metric will falsely try to use as many places as they see in the calculator's display. There is such a thing as significant digits. If the digits aren't significant to the application, they can be dropped. > > It is best to round numbers to the nearest mark that appears on a ruler. Trying to make something 3.3 mm long, where the 0.3 mm mark is a guess, makes the extra digit useless. If the ruler is accurate to 0.5 mm or a micrometer is used to measure, and the degree of precision requires great accuracy, then the extra digits are needed. But, in most applications, they are not. > > Writing numbers like 3.33333 mm when not necessary will scare off those not yet committed to metric. They may see metric as complicated. We need to present it to them in an easy manner. > > As for using 250 m instead of 1/4 km (BTW, it is "km" and not "KM") is also part of a rule. Numbers should fall between 1 and 1000. Use the appropiate prefix to bring the number into this range. > > Unlike imperial where a 1/4 mile would be hard to convert to feet, metric units are easy to interconvert. If you think in quarter kilometres, but see or have to used the standard format, you can mentally do the conversions in milliseconds. > > There is a reason for rules in metric, just like there are rules for grammar and spelling. They facilitate understanding and reduce misunderstanding and errors. > > --------------------------------------------- > DO NOT REPLY TO THIS MESSAGE BY EMAIL! > --------------------------------------------- > You have chosen to receive messages from "Metric America" by email. > > Reply to this message: > http://clubs.yahoo.com/clubs/metricamerica/bbsfrp?action=r&tid=metricamerica &sid=12177109&mid=943 > > Unsubscribe from the Club mailing list: > http://clubs.yahoo.com/clubs/metricamerica/config/change_mb_list > > Return to "Metric America": > http://clubs.yahoo.com/clubs/metricamerica > ---------------------------------------------- > > Not a member? Remove yourself from this list: > http://edit.clubs.yahoo.com/config/unsubscribe_mb_list?.userID=millitesla&.g roupID=metricamerica&.groupType=&.code=kqkKEmys7C > >
