Determining Sig Figs

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RandallNeeDis3K
Posts: 34
Joined: Fri Sep 28, 2018 12:25 am

Determining Sig Figs

Postby RandallNeeDis3K » Thu Oct 04, 2018 8:09 pm

I get confused on when to "obey" the sig figs given in a question, and when not to. I overheard someone saying if there's multiplication, then you use the sig figs given in the question? Can someone clarify this for me, thanks.

MichelleRamirez_2F
Posts: 63
Joined: Fri Sep 28, 2018 12:28 am

Re: Determining Sig Figs

Postby MichelleRamirez_2F » Thu Oct 04, 2018 8:19 pm

When you are multiplying you must use the smallest number of significant figures in your data to be the number of significant figures in your answer. For example, if you are multiplying 6.18165 x 3.56=22.0 your answer must only have 3 significant figures since that is the smallest number of significant figures that shows up in your original data(numbers).

MichelleRamirez_2F
Posts: 63
Joined: Fri Sep 28, 2018 12:28 am

Re: Determining Sig Figs

Postby MichelleRamirez_2F » Thu Oct 04, 2018 8:22 pm

You may also want to refer to Dr. Lavelle's "Math Assistance" section where he has two documents that goes over the use of significant figures thoroughly!

Becky Belisle 1A
Posts: 81
Joined: Fri Sep 28, 2018 12:18 am

Re: Determining Sig Figs

Postby Becky Belisle 1A » Thu Oct 04, 2018 8:25 pm

I think it's best to use sig figs in all problems. When doing addition or subtraction, the number with the least digits after the decimal determines how many digits can be after the decimal. For Example: 1.82 + 2.1 = 3.9.

Tatum Keichline 2B
Posts: 64
Joined: Fri Sep 28, 2018 12:26 am

Re: Determining Sig Figs

Postby Tatum Keichline 2B » Thu Oct 04, 2018 8:33 pm

Sigfigs should always match the lowest significant number given in the problem. For example, if a problem has 3.2+4.88=?, your answer should be rounded to two sigfigs.

Jacqueline Duong 1H
Posts: 61
Joined: Fri Sep 28, 2018 12:28 am

Re: Determining Sig Figs

Postby Jacqueline Duong 1H » Fri Oct 05, 2018 5:44 pm

When you are multiplying or dividing, the number of sig figs in your answer is determined by the number with the least amount of sig figs. However, when you are adding or subtracting, the number of decimal places in the answer is determined by the smallest number of decimal places in the problem.

Raj_Bains_2C
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Joined: Fri Sep 28, 2018 12:25 am
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Re: Determining Sig Figs

Postby Raj_Bains_2C » Fri Oct 05, 2018 5:55 pm

It is best to obey the rules of significant figures all the time to retain the accuracy of measurements. It might help you to review the basic rules of significant figures.
Examples: 5.48 x 6.2 = 34 8.2 x 0.6 = 5 9.01 x 2.333 = 21.0


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