Rounding answers

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jordanginyard_
Posts: 81
Joined: Wed Sep 30, 2020 9:43 pm

Rounding answers

Postby jordanginyard_ » Sun Oct 11, 2020 11:19 pm

When we have an answer to any problem and we have to round. What should we round up to? Should I have round up to the tenths or hundredths?

Hannah Alltucker 3L
Posts: 106
Joined: Wed Sep 30, 2020 9:44 pm

Re: Rounding answers

Postby Hannah Alltucker 3L » Sun Oct 11, 2020 11:41 pm

You should round based on your smallest sig figs from the information that the problem itself gives you. They represent the accuracy of your measurements, so you can only be as accurate as what is already given.

OwenSumter_2F
Posts: 92
Joined: Wed Sep 30, 2020 9:57 pm
Been upvoted: 2 times

Re: Rounding answers

Postby OwenSumter_2F » Mon Oct 12, 2020 1:53 pm

Also, as an additional note, try not to round your numbers until the final answer, otherwise you could be off by a few decimal points.

Mikayla Kwok 3K
Posts: 99
Joined: Wed Sep 30, 2020 9:51 pm

Re: Rounding answers

Postby Mikayla Kwok 3K » Tue Oct 13, 2020 12:40 am

Just an additional note about rounding that was new to me upon entering this class: when you round based on the smallest number of sig figs and the digit immediately after your last is 5, you do not always round up. You round to the nearest even number. For instance, if you get an exact answer of 2.45 g, and you need to round off to 2 sig figs, your final answer would be 2.4, not 2.5, because 4 is the closest even number.

Tanya Nguyen 1B
Posts: 91
Joined: Wed Sep 30, 2020 9:33 pm

Re: Rounding answers

Postby Tanya Nguyen 1B » Tue Oct 13, 2020 7:20 pm

When calculating I try to use as many decimal places as I can (usually four to five decimal places) to get the most accurate answer. For the answer, I would round it to however many sig figs was given in the question.

Queena Chu 3E
Posts: 86
Joined: Wed Sep 30, 2020 10:09 pm

Re: Rounding answers

Postby Queena Chu 3E » Sun Oct 18, 2020 7:26 pm

Typically, I avoid rounding until the end of the problem so I can get as precise of an answer as possible. I usually leave 6 decimal points and then when I finish all my calculations, I round based on the number of sig figs given in the problem.

Kathy_Li_1H
Posts: 90
Joined: Wed Sep 30, 2020 9:31 pm

Re: Rounding answers

Postby Kathy_Li_1H » Thu Oct 22, 2020 6:36 pm

Hi! I would suggest NOT rounding any calculated value until you find the answer, preventing calculation errors, and when you get your answer, round your answer to the smallest sig fig. Hope this helps!

James Patanian 2C
Posts: 54
Joined: Wed Sep 30, 2020 9:55 pm

Re: Rounding answers

Postby James Patanian 2C » Thu Oct 22, 2020 8:42 pm

Hi, do we need to know how to round sig. figs when dealing with logarithms for the midterm? Will we be dealing with logarithms much at all in this level of chemistry?


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