When should I start looking at sig figs?
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When should I start looking at sig figs?
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?
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Re: When should I start looking at sig figs?
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 :)
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Re: When should I start looking at sig figs?
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.
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Re: When should I start looking at sig figs?
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!
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Re: When should I start looking at sig figs?
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!
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Re: When should I start looking at sig figs?
I think looking to make sure your sig figs are aligning correctly is most important when you get your final answer!
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Re: When should I start looking at sig figs?
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.
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Re: When should I start looking at sig figs?
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.
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Re: When should I start looking at sig figs?
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.
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.
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Re: When should I start looking at sig figs?
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.
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Re: When should I start looking at sig figs?
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
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Re: When should I start looking at sig figs?
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.
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.
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Re: When should I start looking at sig figs?
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.
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Re: When should I start looking at sig figs?
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.
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Re: When should I start looking at sig figs?
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!
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Re: When should I start looking at sig figs?
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.
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Re: When should I start looking at sig figs?
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.
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Re: When should I start looking at sig figs?
like everyone said, I usually don't worry about sig figs until I have my final answer!
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Re: When should I start looking at sig figs?
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!
Re: When should I start looking at sig figs?
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.
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Re: When should I start looking at sig figs?
I agree with many others who have posted. On the calculator, I try to keep everything as precise as possible until the final sum.
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Re: When should I start looking at sig figs?
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 :)
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Re: When should I start looking at sig figs?
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
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Re: When should I start looking at sig figs?
Hi, I normally don't round to the number of sig figs need until the final answer. Hope that helps!
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Re: When should I start looking at sig figs?
I think just using sig figs in your final answer is fine!
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Re: When should I start looking at sig figs?
Hi! I use exact numbers during calculations and wait till my final answer to round.
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Re: When should I start looking at sig figs?
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.
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Re: When should I start looking at sig figs?
Graphing calculators are my saving grace here, I just save all rounding until the very end.
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Re: When should I start looking at sig figs?
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.
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Re: When should I start looking at sig figs?
I would solve and keep all of the numbers that show up on your calculator value and then at the end determine sig figs.
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Re: When should I start looking at sig figs?
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.
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Re: When should I start looking at sig figs?
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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