When are zeroes significant in calculations?

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RobertXu_2J
Posts: 104
Joined: Fri Aug 30, 2019 12:17 am

When are zeroes significant in calculations?

Postby RobertXu_2J » Wed Oct 02, 2019 11:41 pm

I'm confused. Sometimes zeroes are counted as significant and sometimes they are not. Does it depend on the position of the zero?

Myka G 1l
Posts: 100
Joined: Fri Aug 30, 2019 12:17 am

Re: When are zeroes significant in calculations?

Postby Myka G 1l » Wed Oct 02, 2019 11:45 pm

Yes, zeroes in between two numbers and any final or trailing zeroes(occurring at the end of the decimal) are also significant.

JustinHorriat_4f
Posts: 111
Joined: Wed Sep 18, 2019 12:19 am

Re: When are zeroes significant in calculations?

Postby JustinHorriat_4f » Wed Oct 02, 2019 11:45 pm

Yes sometimes zeros are included and sometimes they are not. You only include zeros when they are after a decimal(trailing zeros) and in between numbers. Therefore, 20.0 has 3 sig figs, and 204.05 has 5 sig figs. However, zeros before numbers in a decimal are not significant such as 0.006 only has 1 sig fig.

Jainam Shah 4I
Posts: 130
Joined: Fri Aug 30, 2019 12:16 am

Re: When are zeroes significant in calculations?

Postby Jainam Shah 4I » Wed Oct 02, 2019 11:47 pm

Yes, it does depend on the position of the zero. For example, in a number like 505 the zero is in between two digits making it significant. So 505 would have three sig figs. Zeros that are trailing or the last zero do count. For example in 0.00500, the last two zeros are considered significant. However, the first two zeros are place holders and would not count.

Elizabeth Johnson 1I
Posts: 53
Joined: Wed Sep 11, 2019 12:16 am

Re: When are zeroes significant in calculations?

Postby Elizabeth Johnson 1I » Wed Oct 02, 2019 11:50 pm

The zeroes at the end of a number (past the decimal) signify more precision, so a measurement of 20.0000 ml (6 sig figs) is more precise than a measurement of 20.0 ml (three sig figs), even though to the layperson they would mean the same thing. A measurement of 20 ml would only have 1 sig fig. If it begins a number like with 0.00008, the zeroes mean diddly squat before the 8. There is only one sig fig there.

Varadhan_3G
Posts: 49
Joined: Wed Sep 18, 2019 12:20 am

Re: When are zeroes significant in calculations?

Postby Varadhan_3G » Wed Oct 02, 2019 11:53 pm

Zeroes are significant when:

They are found in-between significant digits, E.g. : 405, 20,001 (3 sig figs and 5 sig figs respectively)

A final/trailing '0' after a decimal point and a non-zero value, E.g. : 0.00060, 1.40 x 10^2 (2 sig figs and 3 sig figs respectively). A decimal place after zeroes in a value above zero, such as 100. can be used to make the zeroes significant--100. has 3 sig figs.



Zeroes are not significant when:

They are in front of a value lower than 0, E.g. : 0.00060. This would only be 2 sig figs because the four zeroes in front of the value are in front of the non-zero value.


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