If you have a number like "200" and you have the same number but with a decimal, "200." Which one has one significant figure and which has three sig. figs?
(This is is more of a chemistry question, but there's no category for that :P)

Question

amistre64 · Answer

a sig fig is all the figs that are needed to make a coherent discription of the number being used

anonymous · Answer

So, does that mean that 200. has three significant figures while 200 only has one?

anonymous · Answer

200 has 1 significant figure
200.decimal has 3 significant figures
all zeros between nonzero numbers are significant figures

amistre64 · Answer

id say each number has 3 ... but they may have changed the terminology on me over the years :)

anonymous · Answer

Ok, but then 200.0 has four sig figs right? And thanks amistre, the people I asked had the same answer

anonymous · Answer

You can indicate which is the final sig fig by punctuation:  place a bar over it.

anonymous · Answer

well i think the convention is that 200 has only 1 significant figure. because 200 can mean 150 to 249 or 195 to 204 or 199.5 to 200.4, but I assume that it has the least number of significant figure possible, 1

anonymous · Answer

Ok, thanks. So as my problem states, if I were to "Write the numbers 10, 100, and 1000 in scientific notation with two, three, and four significant figures, respectively," then would my first answer be 10. * 10^0 ?

anonymous · Answer

No.

anonymous · Answer

Or 1 * 10^1 ?

anonymous · Answer

1x10^1

anonymous · Answer

and so forth...

anonymous · Answer

Wait but doesn't 1 only have one sig fig?

anonymous · Answer

I'm confused >_<

anonymous · Answer

1.0 x 10^1 and so on... I really found this helpful when I was stumped on sig fig: See 5:42 in http://www.khanacademy.org/video/more-on-significant-figures?playlist=Pre-algebra

anonymous · Answer

Sorry about my prior typo - and good catch on your part.

anonymous · Answer

This is the one he mentions at about 5:50 in the other one: http://www.khanacademy.org/video/scientific-notation-1?playlist=Algebra%20I%20Worked%20Examples

anonymous · Answer

Best wishes, I need to go back to my studies.

anonymous · Answer

Ahh now it's making sense, so 100 in scientific notation with 2 sig figs would be 1.00 * 10^2 right?

anonymous · Answer

Yes

anonymous · Answer

1.0 I think is enough.

anonymous · Answer

Thanks so much I really appreciate your help!

anonymous · Answer

Def check the vid I sent, it is where I learned this stuff (again after 30 years out of school).

anonymous · Answer

I will. Thanks again!