subtracting with sig figs

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Joseph Saba
Posts: 154
Joined: Thu Jul 11, 2019 12:16 am

subtracting with sig figs

Postby Joseph Saba » Thu Oct 03, 2019 4:41 pm

2.026-1.0579= ?, I am not too sure about whether or not we round to the last digit or whether to the lowest number of sig figs a given measurement has.

Kavya Immadisetty 2B
Posts: 106
Joined: Sat Aug 24, 2019 12:17 am
Been upvoted: 1 time

Re: subtracting with sig figs

Postby Kavya Immadisetty 2B » Thu Oct 03, 2019 4:45 pm

You're supposed to round to the smallest number of digits after the decimal point. Because 2.026 has 3 digits after the decimal and 1.0579 has 4 digits after the decimal, the answer should have 3 digits after the decimal. The answer is 0.968

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

Re: subtracting with sig figs

Postby KarineKim2L » Thu Oct 03, 2019 5:00 pm

When multiplying or dividing, you pay attention to the number with the least amount of sig figs, but when you do addition or subtraction, you pay attention to the number with the least values past the decimal point.

ashwathinair
Posts: 113
Joined: Sat Aug 17, 2019 12:17 am

Re: subtracting with sig figs

Postby ashwathinair » Thu Oct 03, 2019 5:12 pm

KarineKim1L wrote:When multiplying or dividing, you pay attention to the number with the least amount of sig figs, but when you do addition or subtraction, you pay attention to the number with the least values past the decimal point.


Wait but we only have to round/truncate for the final answer to a question right? What happens if you use both multiplication/division and addition/subtraction in a question?

Nare Arakelian Dis 3E
Posts: 58
Joined: Thu Jul 11, 2019 12:16 am

Re: subtracting with sig figs

Postby Nare Arakelian Dis 3E » Thu Oct 03, 2019 10:58 pm

So with adding and subtracting is the rule that the answer should have the same number of decimal places as the number with the least decimal places or should have the same number of sig figs overall as the number with the least number of decimal places?

Siddiq 1E
Posts: 106
Joined: Fri Aug 09, 2019 12:15 am

Re: subtracting with sig figs

Postby Siddiq 1E » Thu Oct 03, 2019 11:07 pm

My understanding: for adding and subtracting, look at numbers beyond the decimal point. for multiplying and dividing, look at the amount of sig figs based on the other rules (ex, zeroes and amount presented in the problem) is this correct?


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