How would you round these numbers

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Gillian Gabrielsen2F
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How would you round these numbers

Postby Gillian Gabrielsen2F » Tue Oct 20, 2020 4:03 pm

How do you round numbers such as 7.956 and 4.9773 to two sigfigs? I normally round to 8.0 or 5.0 but that seems incorrect

Sabina House 2A
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Re: How would you round these numbers

Postby Sabina House 2A » Tue Oct 20, 2020 4:05 pm

I believe that rounding those answers to 8.0 and 5.0 is correct if using two sig figs.

Hannah Lechtzin 1K
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Re: How would you round these numbers

Postby Hannah Lechtzin 1K » Tue Oct 20, 2020 4:25 pm

8.0 and 5.0 would be correct if you are rounding to two sig figs

Brendan Duong 1I
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Re: How would you round these numbers

Postby Brendan Duong 1I » Wed Oct 21, 2020 11:07 am

Recall you always round either up or down the last significant figure!

Abby Lam 3F
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Re: How would you round these numbers

Postby Abby Lam 3F » Wed Oct 21, 2020 11:12 am

I think you are correct. The zero in that case counts as a sig fig.

Inderpal Singh 2L
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Re: How would you round these numbers

Postby Inderpal Singh 2L » Wed Oct 21, 2020 1:17 pm

8.0 and 5.0. Remember that any zero's at the end of a number after a decimal point count as a significant figure :)

Alex Mele 2A
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Re: How would you round these numbers

Postby Alex Mele 2A » Wed Oct 21, 2020 1:22 pm

Your numbers are correct! For more information about rounding and sig figs in general, the link on Dr. Lavelle's website is short and really helpful. https://lavelle.chem.ucla.edu/wp-conten ... OUT_SF.pdf

Chinyere Okeke 2J
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Re: How would you round these numbers

Postby Chinyere Okeke 2J » Sat Oct 24, 2020 4:37 pm

The way you rounded it is correct. I also get nervous when rounding numbers with sigfigs like that. But you should remember to round only at the end when you have your answer because rounding in the intermediate steps could cause you to get the wrongs answer.

Gicelle Rubin 1E
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Re: How would you round these numbers

Postby Gicelle Rubin 1E » Sat Oct 24, 2020 7:57 pm

You actually did it correctly!! I also had my doubts about my rounding at first.

Dane_Beasley_1E
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Re: How would you round these numbers

Postby Dane_Beasley_1E » Sun Oct 25, 2020 8:49 pm

Rounding those numbers to 8.0 and 5.0 would be correct. Zeroes following a number 1-9 count as a significant figure when there is a decimal.

Jeffrey Fenn 1G
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Re: How would you round these numbers

Postby Jeffrey Fenn 1G » Sun Oct 25, 2020 8:51 pm

Professor Lavelle has a really good lesson on sig figs on his website that really helped me!


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