Simple average question using sig figs within ± 0.0 of uncertainty?

AI Thread Summary
The discussion revolves around calculating the average mileage from a set of measurements while considering significant figures and the specified uncertainty of ± 0.0 mph. The average mileage was initially calculated as 26.60833333, but confusion arose regarding the interpretation of "within ± 0.0 mph." It was clarified that this means the answer should be presented with one decimal place, effectively rounding to 26.6 mph. The final consensus is that the correct average mileage, adhering to the significant figures rule and the specified uncertainty, is 26.6 ± 0.0 mph. This highlights the importance of understanding how to apply significant figures in calculations involving uncertainty.
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Simple average question using sig figs within ± 0.0 ?

Homework Statement



Consider the following measurements of mileages:
23.8 mph, 20.1 mph, 26.5 mph, 20.7 mph, 21.7 mph, 27.6 mph,
30 mph, 28 mph, 27.4 mph, 34.3 mph, 26.5 mph, 32.7 mph.
What is the average mileage (using sig figs)?

Answer in units of mph Your answer must be within ± 0.0 mph.

Homework Equations



Avg=Total Sum/number of variables


The Attempt at a Solution



The average calculated was 26.60833333. And Since two variables have only two sig figs, I thought the answer should be 27. But it was a wrong answer.
But the last part of question asked the answer to be within ± 0.0 mph.

What does 'within ± 0.0 mph' means? No uncertainty? Or typo of 0.1 or 0.01?
What should be the correct answer?
 
Last edited:
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Welcome to PF, bobi! :smile:

'within ± 0.0 mph' means within ± 0.05 mph.
That is, with 1 digit after the decimal point.
So your average would be 26.6 ± 0.0 mph
 
I like Serena said:
Welcome to PF, bobi! :smile:

'within ± 0.0 mph' means within ± 0.05 mph.
That is, with 1 digit after the decimal point.
So your average would be 26.6 ± 0.0 mph

Thanks a lot!
 

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