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

[bobi]

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?

 

[I like Serena]

Welcome to PF, bobi!

'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

 

[bobi]

Welcome to PF, bobi!

'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!