Sig Figs in Mulitstep Problems

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KarineKim2L
Posts: 100
Joined: Fri Aug 30, 2019 12:16 am

Sig Figs in Mulitstep Problems

Postby KarineKim2L » Thu Oct 03, 2019 5:14 pm

For multi-stage problems, are sig figs only graded for the final solution? Is it best to keep lots of figures for all of the steps and only round the final answer?

vpena_1I
Posts: 109
Joined: Sat Aug 24, 2019 12:15 am

Re: Sig Figs in Mulitstep Problems

Postby vpena_1I » Thu Oct 03, 2019 5:17 pm

It's best to keep as many figures as you can when doing the calculations and then rounding off the final answer to the necessary sig figs. With some calculators, its easy to carry over large numbers with the [ans] button.

zfinn
Posts: 106
Joined: Fri Aug 30, 2019 12:16 am

Re: Sig Figs in Mulitstep Problems

Postby zfinn » Thu Oct 03, 2019 5:18 pm

I'm not sure what Dr.Lavelle prefers for his class, but I usually keep more sigfigs than needed during the process of the problem (for accuracy) and then round to correct sigfigs for my final answer.

Jacob Puchalski 1G
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Joined: Fri Aug 09, 2019 12:16 am

Re: Sig Figs in Mulitstep Problems

Postby Jacob Puchalski 1G » Thu Oct 03, 2019 5:19 pm

I think it's best to round throughout the steps to an extent; we should round enough so that it's easier to keep track of the numbers but not so much that it'll affect the final answer. Maybe around four sig figs?

405268063
Posts: 102
Joined: Thu Jul 25, 2019 12:17 am

Re: Sig Figs in Mulitstep Problems

Postby 405268063 » Thu Oct 03, 2019 5:33 pm

Yes, that's what I would do. Keep more figures than you know you need for the sig figs at the end of the problem (you can figure this out by looking at the numbers given in the problem) and then round at the very end for your solution.

Michelle Le 1J
Posts: 50
Joined: Fri Aug 09, 2019 12:16 am

Re: Sig Figs in Mulitstep Problems

Postby Michelle Le 1J » Thu Oct 03, 2019 5:38 pm

Yes, I agree with the previous responses because it doesn't hurt to have more sigfigs than you need during your calculations, but it will mess them up if you accidentally rounded up a number.

mayarivers3I
Posts: 52
Joined: Wed Sep 18, 2019 12:18 am

Re: Sig Figs in Mulitstep Problems

Postby mayarivers3I » Thu Oct 03, 2019 6:57 pm

When I do sig figs for multistep problems, I don't round until the final answer because it's easier to continue the calculations on a calculator and your final answer will be more accurate.

305416361
Posts: 50
Joined: Fri Aug 09, 2019 12:17 am

Re: Sig Figs in Mulitstep Problems

Postby 305416361 » Fri Oct 04, 2019 2:06 pm

Also one thing to keep in mind is that most graphing calculators have a sig fig function if you're using those for homework problems, but we're not allowed to use those on exams, so it's probably better to just get in the habit of keeping more sig figs throughout the problem and then rounding at the end.

HannahBui 2K
Posts: 101
Joined: Wed Sep 18, 2019 12:19 am

Re: Sig Figs in Mulitstep Problems

Postby HannahBui 2K » Fri Oct 04, 2019 3:27 pm

It's best to keep as many sig figs as possible while going through the steps of a problem and only round once you've gotten your final answer!

stephaniekim2K
Posts: 79
Joined: Fri Aug 09, 2019 12:16 am

Re: Sig Figs in Mulitstep Problems

Postby stephaniekim2K » Sat Oct 05, 2019 7:51 pm

Personally, I have a calculator that keeps track of all the problems I did previously (TI-84), so what I do is when I am doing work on paper, I will write the answer (throughout the problem not the final answer) with the amount of sig figs that are called for, but when I am calculating the next portion, I will use the full number that isn't rounded.

For example, if I was working through a problem

(1.12)(2.338)=2.62

I would write it down like this (above) on my paper, but on my calculator (say I needed to do another part) I would put this

2.61856 .......

the whole number instead of the rounded 2.62.

emwoodc
Posts: 45
Joined: Fri Aug 09, 2019 12:16 am

Re: Sig Figs in Mulitstep Problems

Postby emwoodc » Sun Oct 06, 2019 11:09 pm

Yes, if you round the sig figs too early in the problem, it could produce an answer that's one or two numbers off


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