When to use sig figs

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Lea Ozdere 2G
Posts: 98
Joined: Wed Sep 30, 2020 9:42 pm

When to use sig figs

Postby Lea Ozdere 2G » Fri Oct 23, 2020 12:07 am

Are we supposed to be keeping track of sig figs throughout a problem whenever we do any type of mathematical calculation, or do we just apply sig figs at the very end with our final answer?

Ethan Laureano 3H
Posts: 92
Joined: Wed Sep 30, 2020 9:58 pm

Re: When to use sig figs

Postby Ethan Laureano 3H » Fri Oct 23, 2020 12:09 am

I usually write out the full number each time and then apply the sig figs at the end. That way, I can ensure I get the most accurate number.

Allan Nguyen 2G
Posts: 95
Joined: Wed Sep 30, 2020 9:49 pm

Re: When to use sig figs

Postby Allan Nguyen 2G » Fri Oct 23, 2020 12:13 am

I believe that in the middle of calculations, you wouldn't round down values to sig figs. However, when calculating your final answer, you would then use sig figs because if you used sig figs in the middle of the problem and then used those values to calculate the solution, the answer would be less accurate. Basically, what I'm trying to say is that always use the stored values in your calculator, and then show your final answer in sig figs.

Natalie Phan 3G
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Joined: Wed Sep 30, 2020 9:48 pm

Re: When to use sig figs

Postby Natalie Phan 3G » Fri Oct 23, 2020 2:54 am

I think the best way to apply sig figs is at the very end, on your final answer. If you round too many times during the actual calculations the final answer may be way off. If you can save all your numbers on your calculator, that's great but if not, I think 4-5 decimal places should be good enough. And for problems that don't really give you numbers, 3 sig figs is always a safe bet!

SophiaNguyen_2L
Posts: 104
Joined: Wed Sep 30, 2020 9:59 pm

Re: When to use sig figs

Postby SophiaNguyen_2L » Fri Oct 23, 2020 9:56 am

During my discussion section, my TA applied sig figs once we were finished with our calculations. I think the answer is more precise that way.

David Facio 1K
Posts: 41
Joined: Wed Sep 30, 2020 9:38 pm

Re: When to use sig figs

Postby David Facio 1K » Fri Oct 23, 2020 10:17 am

Yes, I concur with everyone else. Both TA's and LA's have unanimously recommended completing the problem with full values for calculations, and then applying sig fig rules to your final answer. This ensures the most accurate answer. I was confused by this for a while too! Great Question!

Justin Lin 1B
Posts: 95
Joined: Wed Sep 30, 2020 9:50 pm

Re: When to use sig figs

Postby Justin Lin 1B » Fri Oct 23, 2020 10:30 am

My TA said that it's best to apply sig figs until you get your final answer

Kayla Booker 1F
Posts: 90
Joined: Wed Sep 30, 2020 9:43 pm

Re: When to use sig figs

Postby Kayla Booker 1F » Fri Oct 23, 2020 11:14 am

I think the best way is to apply sig figs at the very end otherwise your answer might be off by a little

Charmaine Ng 2D
Posts: 98
Joined: Wed Sep 30, 2020 9:37 pm

Re: When to use sig figs

Postby Charmaine Ng 2D » Fri Oct 23, 2020 12:14 pm

Yep, I think you just apply sigfigs at the end, so that the answer doesn't become too different with all the rounding and can remain as accurate as possible!!

Chem_Mod
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Re: When to use sig figs

Postby Chem_Mod » Fri Oct 23, 2020 12:22 pm

Please do not round until the end! It should be fairly easy to store values in your calculator. Then, provide your final answer to the correct number of sig figs!

Colin Squire 3B
Posts: 90
Joined: Wed Sep 30, 2020 9:35 pm

Re: When to use sig figs

Postby Colin Squire 3B » Fri Oct 23, 2020 12:54 pm

If there are multiple answers that I have to solve for in order to get an final answer, I only apply significant figures to the final answer. The initial answers that help me get to the final one aren't rounded.

derickngo3d
Posts: 80
Joined: Wed Sep 30, 2020 9:51 pm

Re: When to use sig figs

Postby derickngo3d » Fri Oct 23, 2020 12:58 pm

I usually apply sig figs at the end of the problem.

Rose_Malki_3G
Posts: 127
Joined: Wed Sep 30, 2020 10:02 pm

Re: When to use sig figs

Postby Rose_Malki_3G » Fri Oct 23, 2020 2:04 pm

You should only round your numbers to the correct number of sig figs once you have found your final answer

Vanshika Bhushan 1A
Posts: 95
Joined: Wed Sep 30, 2020 9:33 pm

Re: When to use sig figs

Postby Vanshika Bhushan 1A » Fri Oct 23, 2020 10:30 pm

You should apply significant figures at the end of the problem because that way if someone were to redo the problem using your work, they would get the same answer. Using sig figs as you work through the problem will cause your answer to vary from the actual answer.

Jada3J
Posts: 95
Joined: Wed Sep 30, 2020 9:34 pm

Re: When to use sig figs

Postby Jada3J » Sun Oct 25, 2020 8:41 pm

Regarding the Midterm, many of the UAs and TAs are saying that sig figs are not to be concerned about in the final answer due to it being multiple choice.

Lily Anne Garcia 1C
Posts: 88
Joined: Wed Sep 30, 2020 9:55 pm

Re: When to use sig figs

Postby Lily Anne Garcia 1C » Sun Oct 25, 2020 8:44 pm

To avoid round off error, use the whole number until your very last calculation. If you need to write down numbers for problems with multiple steps, you can round them on paper, but keep the entire number on your calculator so you can produce a more accurate answer at the end.

Jeffrey Fenn 1G
Posts: 53
Joined: Wed Sep 30, 2020 10:08 pm

Re: When to use sig figs

Postby Jeffrey Fenn 1G » Sun Oct 25, 2020 8:53 pm

For me it has always been really easy to maintain sig figs through every part of the problem, because it just takes away the extra stress of conversion when finishing the problem.

LovepreetSran_3H
Posts: 76
Joined: Wed Sep 30, 2020 9:33 pm

Re: When to use sig figs

Postby LovepreetSran_3H » Sun Oct 25, 2020 9:06 pm

I normally apply sig figs at the end when I get my final answer.

Aria Movassaghi 1A
Posts: 97
Joined: Wed Sep 30, 2020 9:40 pm

Re: When to use sig figs

Postby Aria Movassaghi 1A » Sun Oct 25, 2020 10:07 pm

To be safe, keep everything exact until the final answer and then worry about sig figs.

jia207
Posts: 101
Joined: Wed Sep 30, 2020 9:52 pm

Re: When to use sig figs

Postby jia207 » Sun Oct 25, 2020 10:29 pm

I believe for the midterm, we won't have to worry about sig figs as much because all the answers will be in multiple choice. That being said, I think it is still important to use sig figs throughout the problem.


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