(adsbygoogle = window.adsbygoogle || []).push({}); significant figures help needed badly!!

hows everyone doing in this fine evening?

ok i just had some questions on "sig figs" as the pros call it (unfortunately that's not me ) ok, i'll try to explain as clearly as i can here:

in this manual i have that explains sig figs, it says the following aboutSiginificant Figures in Logarithms:

...The)characteristicconsists of the digits to the lft of the decimal point and themantissaconsists of the digits to the right of the decimal point. the mantissa of a log should have the same number of sig. figs. as does the original number. Some esamples are:

log 2=0.3 (1sig fig in 2)

log 2.0=0.30 (2 sig figs in 2.0)

log 2.00=0.300 (3 sig figs in 2.00

log 2.0 X 10^4=4.30 (2 sig figs in 2.0)

log 2.00 X 10^(-5)=-4.699 (3 sig figs in 2.00)

now my questions concern the red bold faced part of the above examples. if it says that there's "3 sig figs in 2.00" then why does it report a four sig fig carrying number -4.699??????? :surprised :yuck: :uhh:

it said that the same rule was applied to antilogs, but again, same problem a little further down in the examples:

... antilog 3.4771 = 3.000 X 10^3 (4 sig figs in the mantissa)

uh yea i see that but so what?? isn't it supposed to have FIVE sig figs because of the "characteristic"??

also, can somebody please tell me if i did these correctly:

Round to four sig figs:

273.15-> 273.2 *(bcuz the "1" is an odd number, you would round up to the nearest even number, right? and if it was already an even number followed by a 5 and nothing else following the 5, you would leave it alone as a "1" and jsut drop the five, right??

12.652-> 12.65

19.9743-> 19.97

4.32156-> 4.322

0.019807-> 0.01981

Thanks!!!

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# Homework Help: Significant figures help needed badly

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