DEFINITIONS AXD EXPLANATIONS 



UNDKKI.Yl.M, TIIK COMPUTATION BULBS. 



following statements call for the attention of those only who find 

 unfaiiiilar terms in the foregoing rules. 



A Digit is any one of the ten characters i, 2, 3, 4, 5, 6, 7, 8, 9, o. 

 A Significant Figure is any digit used to denote or signify tin- amount of the 

 quantity in tin- place in which it stands. Thus zero may In- a siu'iiilicai;: 

 when it is written nut merely to locate tin- decimal point, but to indicate that 

 intity in the place in which it stands is known to be nearer to /,-ro than 

 to any other d: 



;.ple, if a distance has been measured to the nearest lifticth of an 

 .d found to be 20546 inches, all live of the figures, inchi'i ro, are 



significant. And similarly if the measurement had shown the diftl 



to 205.40 than to 205.41 or to 205.39 tin- /?///!/ zrm would be also siu'nili- 



;!ld ahnn''' . since its presence Serves the Illo>t 



purpose of iiat this place of figures had been measured as well as 



the rest. If in such a case the quantity had be.-n written 205.4 in-lead <>f 205.40, 



drawn either that the hundredths of an inch had n 



measured, or that tin- pi-rson who wrote the number was ignorant >r car 

 the pr- usage. Failure to follow this simple rule is a common 



.inty. 



r when used mei. >le the decimal point t<> be retain. | 



course not a significant figure in tin If the distan< 



measured as 286. <-entim. ires within i centimetiv. it miuht be retaine.l u 

 2.86 metres, or o.oo 286 kil"metre<. ..r 2S(x). millimetre. In tl iherof 



D this last example it i^ i.bvi..u- that when the tir-t /rro, or zeros, pre- 

 cede the decM ma 1 . fail to indicate intrin>i-ally \\hetheror not they are 



s')0. millimetres or 28600. milliinrires, M 



or the last two pi a In writin- such a niuid" 



:it of the : 



v must be uppi nde.l. This is u>uall 

 re (I to a numb. :res only, repn 



the estimated measure of the accuracy ility <>t th< nsult. s. . 



Places of Figi;- lie places in which figures stand in tin- number R 



actually wi inures are those in \\ nificant 



MIL'' ably. 



