Rounding with basic calculator

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Emily Vainberg 1D
Posts: 102
Joined: Sat Jul 20, 2019 12:15 am

Rounding with basic calculator

Postby Emily Vainberg 1D » Thu Oct 10, 2019 10:43 am

Since we don't have a scientific calculator for tests and quizzes, should we round to a few decimal points after each calculation since the basic calculator can't store the numbers?

005388369
Posts: 73
Joined: Sat Sep 28, 2019 12:16 am

Re: Rounding with basic calculator

Postby 005388369 » Thu Oct 10, 2019 10:59 am

We are allowed to use scientific calculators. We are not allowed to use graphing calculators.

Sahil Jog 1F
Posts: 126
Joined: Thu Jul 11, 2019 12:16 am

Re: Rounding with basic calculator

Postby Sahil Jog 1F » Thu Oct 10, 2019 11:02 am

It's always good to leave a couple of decimal points when computing your answer, as it will get as close to the real answer as possible, however, your final answer should include the correct amount of sig figs.

Veronica_Lubera_2A
Posts: 106
Joined: Sat Sep 14, 2019 12:16 am
Been upvoted: 1 time

Re: Rounding with basic calculator

Postby Veronica_Lubera_2A » Thu Oct 10, 2019 11:09 am

I asked one of the T.A.'s this question and he said that as long as in the steps of your calculation, you use more decimals than the required amount of sig figs, then you should be able to receive the correct answer when rounding at the end.

Audrie Chan-3B
Posts: 50
Joined: Thu Jul 25, 2019 12:17 am

Re: Rounding with basic calculator

Postby Audrie Chan-3B » Thu Oct 10, 2019 12:38 pm

We are allowed to use scientific calculators. When doing calculations, I usually leave 3 or 4 digits after the decimal and then apply sig figs for my last answer.

AlyshaP_2B
Posts: 112
Joined: Wed Sep 18, 2019 12:19 am

Re: Rounding with basic calculator

Postby AlyshaP_2B » Thu Oct 10, 2019 12:44 pm

One of the TA's I asked about sig figs said that it wasn't too big of a deal as long as all of the numbers in your answer were consistent in the number of sig figs used!

Sanjana K - 2F
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Joined: Sat Sep 07, 2019 12:17 am
Been upvoted: 1 time

Re: Rounding with basic calculator

Postby Sanjana K - 2F » Thu Oct 10, 2019 9:44 pm

Use the "Ans" key on your calculator whenever possible. We're allowed to use scientific calculators but not graphing calculators, so you should be able to store values. Also, I generally leave at least 5 numbers after each decimal point (for each step) and apply sig figs at the very end.

Mai V 4L
Posts: 111
Joined: Fri Sep 28, 2018 12:23 am

Re: Rounding with basic calculator

Postby Mai V 4L » Sun Dec 08, 2019 9:08 am

How important are the sig figs for the final, don't want to loose points :-//

Yolanda_Xing_3A
Posts: 43
Joined: Wed Sep 30, 2020 9:52 pm

Re: Rounding with basic calculator

Postby Yolanda_Xing_3A » Fri Oct 09, 2020 8:01 am

I would follow the question. If the numbers provided has three sig numbers, then I would also do three significant numbers. So does conversation units.
:)

Madison Muggeo 3H
Posts: 101
Joined: Wed Sep 30, 2020 9:35 pm

Re: Rounding with basic calculator

Postby Madison Muggeo 3H » Fri Oct 09, 2020 9:17 am

I had a similar question! I tend to make mistakes when I round too soon, so I try to keep at least 2 extra SF in my calculations, then I round for my final answer.

David Y
Posts: 103
Joined: Wed Sep 30, 2020 9:49 pm

Re: Rounding with basic calculator

Postby David Y » Fri Oct 09, 2020 3:58 pm

Yes I would like to add to always make sue you check to ensure you put correct amount of significant figures.

Chris_Butler_1A
Posts: 56
Joined: Wed Sep 30, 2020 9:32 pm

Re: Rounding with basic calculator

Postby Chris_Butler_1A » Fri Oct 09, 2020 9:31 pm

Sanjana K - 2F wrote:Use the "Ans" key on your calculator whenever possible. We're allowed to use scientific calculators but not graphing calculators, so you should be able to store values. Also, I generally leave at least 5 numbers after each decimal point (for each step) and apply sig figs at the very end.

I apologize if this is more obvious but when you finish all of your calculations, do you just use the values in the question to decide how to apply the sig figs, or is there a general rule for specific types of problems?

Veeda Khan 2E
Posts: 52
Joined: Wed Sep 30, 2020 10:00 pm

Re: Rounding with basic calculator

Postby Veeda Khan 2E » Sat Oct 10, 2020 8:38 am

Chris_Butler_1A wrote:
Sanjana K - 2F wrote:Use the "Ans" key on your calculator whenever possible. We're allowed to use scientific calculators but not graphing calculators, so you should be able to store values. Also, I generally leave at least 5 numbers after each decimal point (for each step) and apply sig figs at the very end.

I apologize if this is more obvious but when you finish all of your calculations, do you just use the values in the question to decide how to apply the sig figs, or is there a general rule for specific types of problems?


You just use the values in the question (not including conversion numbers).

Karina Rodriguez 2H
Posts: 50
Joined: Wed Sep 30, 2020 9:34 pm

Re: Rounding with basic calculator

Postby Karina Rodriguez 2H » Sun Oct 11, 2020 4:26 pm

Hi,
We're allowed to use scientific calculators. It's best to include a few decimal places so you can get the most accurate solution when determining significant figures after your calculations are complete.

Jordan_OBrien_2k
Posts: 53
Joined: Wed Sep 30, 2020 9:43 pm

Re: Rounding with basic calculator

Postby Jordan_OBrien_2k » Sun Oct 11, 2020 4:47 pm

I usually keep more decimals than needed when doing calculations so that I can get as close to the real answer as possible, then after doing the last calculation I round to the correct amount of sig figs. This makes it so you can get the correct answer when rounding at the end.

Britney Tran IJ
Posts: 91
Joined: Fri Aug 30, 2019 12:18 am

Re: Rounding with basic calculator

Postby Britney Tran IJ » Sun Oct 11, 2020 6:10 pm

Hi there! so would it be better to round the number or just truncate it?

ZachMLB963
Posts: 5
Joined: Wed Sep 30, 2020 9:56 pm

Re: Rounding with basic calculator

Postby ZachMLB963 » Sun Oct 11, 2020 8:51 pm

Hiya!

It's a good rule of thumb to avoid rounding until a final solution has been obtained. Rounding is different for each question, and depends on the number of significant digits found on the numbers in the problem.


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