When should I start looking at sig figs?

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Ashley Lopez 3J
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When should I start looking at sig figs?

Postby Ashley Lopez 3J » Sun Oct 11, 2020 1:28 am

Whenever I'm solving a question, how do I know I can start looking at Sig figs. In other words, can I do it during my scratch work when I'm trying to figure out the final answer or do I use all numbers and decimals until I get to the final answer and then I use Sig Figs?

kristinalaudis3e
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Re: When should I start looking at sig figs?

Postby kristinalaudis3e » Sun Oct 11, 2020 4:58 am

I think for more accuracy, you should keep all the decimals during intermediate steps and then use sig figs for your final result. For example, if you get an answer during step one and then round it and then use that rounded number for step two and so on, the likelihood of error increases between each step. So I think you should just use sig figs for your answer of the last step :)

Kiyoka Kim 3C
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Re: When should I start looking at sig figs?

Postby Kiyoka Kim 3C » Sun Oct 11, 2020 5:38 am

I don't change the sig figs in any of the values used in the calculation until I get to the answer. Once I find the final answer, I make sure the sig figs of the answer matches the lowest sig figs among the measured values.

Claudia_Danysh_2B
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Re: When should I start looking at sig figs?

Postby Claudia_Danysh_2B » Sun Oct 11, 2020 3:55 pm

I would also say that you should really only worry about sig figs when you're writing down your final answer. I keep every decimal that I can in between calculations since that helps me be more accurate and then once I'm at my answer, I make sure my final answer and the numbers used in the question have the same number of sig figs!

Emma_Barrall_3J
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Re: When should I start looking at sig figs?

Postby Emma_Barrall_3J » Sun Oct 11, 2020 4:16 pm

I would keep as many decimal places as possible and only use correct sig figs in your final answer. When doing calculations on my calculator, I like to copy and paste for the best accuracy!

Maddie Turk Disc 2J
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Re: When should I start looking at sig figs?

Postby Maddie Turk Disc 2J » Sun Oct 11, 2020 4:33 pm

I think looking to make sure your sig figs are aligning correctly is most important when you get your final answer!

miguel zatarain 2B
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Re: When should I start looking at sig figs?

Postby miguel zatarain 2B » Sun Oct 11, 2020 4:40 pm

I agree with everyone in the replies. Since the professor or any TA has mentioned anything about significant figures, I just use it in my final answer just in case they randomly deduct points because of it.

Carolina Gomez 2G
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Re: When should I start looking at sig figs?

Postby Carolina Gomez 2G » Sun Oct 11, 2020 8:51 pm

During the Workshops/ Step-Up sessions, UA's have suggested keeping as many decimal places as possible while doing the work and using corrects significant figures on the final answer. Keeping all decimal places while solving for the answer would allow to get the most accurate answer.

Mackenzie Van Val 3E
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Re: When should I start looking at sig figs?

Postby Mackenzie Van Val 3E » Sun Oct 18, 2020 1:47 am

Hi! As many other commenters under this post have said, I think it is best to try and keep as many places after the decimal as possible while you are doing your work, and then round for sig figs only at the end.

However, I also saw a post by Dr. Lavelle on Chem Community about how many digits to keep while you are doing your work, and his advice was to not be exhaustive with the decimal places you keep. For example, if you will round to 2 sig figs at the end of your work, you can maintain 4 sig figs throughout the work and be fine, i.e. not have rounding errors for your final answer. So, if you don't want to keep writing down 9 digits during your work, Dr. Lavelle says it's okay not to! Just keep enough sig figs that your rounding will be accurate for your final answer.

Veeda Khan 2E
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Re: When should I start looking at sig figs?

Postby Veeda Khan 2E » Sun Oct 18, 2020 8:55 am

If you're not doing anything in the calculator, I usually keep four decimal places for all of my work. Less than that and I get anxious that I'm rounding too much, more than that and it gets confusing and annoying to do problems.

Gillian Gabrielsen2F
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Re: When should I start looking at sig figs?

Postby Gillian Gabrielsen2F » Sun Oct 18, 2020 9:51 am

You should only worry about sigfigs once you have your final answer. Rounding the intermediary steps will lead to slight errors in the final answer. So in other words, leave the really long decimals until your final answer, which should be rounded and in scientific notation

Helena Hu 3E
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Re: When should I start looking at sig figs?

Postby Helena Hu 3E » Sun Oct 18, 2020 3:07 pm

I really recommend using the calculator option that allows you to manipulate your previous answer:
I have a TI 84 calculator, and using this i do [2nd --> answer (above negative sign]), This allows you to add, subtract, multiply, divide, etc. by these long decimals so that you have the precise answer. After this, like everyone else said, I would not look at sig figs until you have the final answer.

rita_debbaneh2G
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Re: When should I start looking at sig figs?

Postby rita_debbaneh2G » Sun Nov 01, 2020 8:39 pm

I think this was mentioned casually in an earlier lecture or module video. But if I were you, I wouldn't do anything with sig figs (as in rounding the numbers) until you have finished all computations. If you're worried about what to write (because sometimes your number has seven numbers after the decimal place), just put down the first three numbers after the decimal place without rounding. But continue calculations with your calculator as if nothing happened and don't exclude what you left out on your paper.

IshanModiDis2L
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Re: When should I start looking at sig figs?

Postby IshanModiDis2L » Sun Nov 01, 2020 8:45 pm

I agree with the person who just commented above me, I believe in a previous lecture Dr. Lavelle mentioned that it is best to not really give much attention to sig figs until after you are done with your final calculation. However, you should just round your numbers to a proper decimal to ensure percent error is at a minimum.

Kiana Javier 3G
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Re: When should I start looking at sig figs?

Postby Kiana Javier 3G » Sun Nov 01, 2020 8:49 pm

I agree with what everyone else has already said before me! Personally, I just keep all my calculations on my calculator (if possible) until I get to the answer. I usually rearrange my equations until it is something I can input to the calculator in one step. Then, I reread the question to determine how many sig figs I should use to record my answer. From experience, I know that rounding can cause your answer to be a bit off from the ones listed in the multiple choice, so to stay as accurate as possible, try to avoid rounding until the end!

Rayna Irving 2C
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Re: When should I start looking at sig figs?

Postby Rayna Irving 2C » Sun Nov 01, 2020 8:51 pm

I agree with everyone here in saying in order to not have a rounding error ruin my answer I usually keep my work and numbers in my calculator and then look for sig figs in the final answer as my last step.

Aria Movassaghi 1A
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Re: When should I start looking at sig figs?

Postby Aria Movassaghi 1A » Sun Nov 01, 2020 8:53 pm

Yea, I think it is best to not round or worry about sig figs until the very final answer. This way you avoid any errors from that.

Britney Tran IJ
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Re: When should I start looking at sig figs?

Postby Britney Tran IJ » Sun Nov 01, 2020 9:59 pm

like everyone said, I usually don't worry about sig figs until I have my final answer!

Bai Rong Lin 2K
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Re: When should I start looking at sig figs?

Postby Bai Rong Lin 2K » Sun Nov 01, 2020 11:01 pm

Ashley Lopez 1H wrote:Whenever I'm solving a question, how do I know I can start looking at Sig figs. In other words, can I do it during my scratch work when I'm trying to figure out the final answer or do I use all numbers and decimals until I get to the final answer and then I use Sig Figs?

I generally use sig fig for the last final answer and base it on the sig figs of the number that the problem give!

105618850
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Re: When should I start looking at sig figs?

Postby 105618850 » Fri Dec 04, 2020 12:36 am

I normally do all the calculations and include significant figures in my final answer. I believe that if you round early in the process, the resulting answer may be a couple decimal places off.

Tanner Bartyczak 1K
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Re: When should I start looking at sig figs?

Postby Tanner Bartyczak 1K » Sun Dec 06, 2020 12:59 am

I agree with many others who have posted. On the calculator, I try to keep everything as precise as possible until the final sum.

Gicelle Rubin 1E
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Re: When should I start looking at sig figs?

Postby Gicelle Rubin 1E » Sun Dec 06, 2020 2:02 am

I always keep as many decimal points while I'm working on the math and once I've got my final answer, I focus on sig figs :)

David Liu 1E
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Re: When should I start looking at sig figs?

Postby David Liu 1E » Sun Dec 06, 2020 2:34 am

My ta mentioned that you would get the best answer by being as exact during calculations and rounding at the end only for the best/safest results

Jeremy Wei 2C
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Re: When should I start looking at sig figs?

Postby Jeremy Wei 2C » Sun Dec 06, 2020 8:55 pm

Hi, I normally don't round to the number of sig figs need until the final answer. Hope that helps!

Alessia Renna 1D
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Re: When should I start looking at sig figs?

Postby Alessia Renna 1D » Sun Dec 06, 2020 9:42 pm

I think just using sig figs in your final answer is fine!

Halle Villalobos 3E
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Re: When should I start looking at sig figs?

Postby Halle Villalobos 3E » Sun Dec 06, 2020 9:44 pm

Hi! I use exact numbers during calculations and wait till my final answer to round.

TiffanyBrownfield 2I
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Re: When should I start looking at sig figs?

Postby TiffanyBrownfield 2I » Sun Dec 06, 2020 10:20 pm

It's best to save the rounding til the end, and use as many decimal spaces as possible in your calculations. This way your final value will be the closest to the actual value and you can adjust the sig figs accordingly.

Hasan Mirza 3F
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Re: When should I start looking at sig figs?

Postby Hasan Mirza 3F » Sun Dec 06, 2020 10:24 pm

Graphing calculators are my saving grace here, I just save all rounding until the very end.

Alan Huang 1E
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Re: When should I start looking at sig figs?

Postby Alan Huang 1E » Sun Dec 06, 2020 10:35 pm

Like others in this thread have said, it's usually best to focus on sig figs once you have your final answer such that your answer is most precise.

Megan ODonnell 3F
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Re: When should I start looking at sig figs?

Postby Megan ODonnell 3F » Sun Dec 06, 2020 10:37 pm

I would solve and keep all of the numbers that show up on your calculator value and then at the end determine sig figs.

Mina Tadros 3L
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Re: When should I start looking at sig figs?

Postby Mina Tadros 3L » Sun Dec 06, 2020 10:39 pm

I always do all the calculations first, and then I look for sig figs at the very end. This allows my answer to be as accurate as possible, with very minimal to no rounding error.

Dane_Beasley_1E
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Re: When should I start looking at sig figs?

Postby Dane_Beasley_1E » Sun Dec 06, 2020 11:28 pm

I would do all calculations first while maintaining all decimal places possible. Then after the solution is found, I would start looking to see what the sig figs would need to be.


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