SOLUTION: Question is as follows: Population is normally distributed. The football coach randomly selected ten players and timed how long eac player took to perform a certain drill. The t

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Question 1178125: Question is as follows: Population is normally distributed.
The football coach randomly selected ten players and timed how long eac player took to perform a certain drill. The times (in minutes) were:
8.3, 7.3, 13.8, 12.6, 11.1, 9.5, 13.7, 14.2, 9.8, 12.6
Determine a 95% confidence interval for the mean time for all players.
I'd appreciate any help! I can't seem to get it, even though I believe I'm doing it correctly.
The multiple choice options are as follows, if it helps:
A. 9.70 to 12.90
B. 13.00 to 9.60
C. 9.60 to 13.00
D. 12.90 to 9.70
Found 2 solutions by Boreal, ewatrrr:
Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website!
the mean is 11.34
s is 2.25
the 95% half-interval is t (0.975, df=9)*s/sqrt(n); t=2.262
=2.262*2.25/sqrt(9)=1.70
add to and subtract from mean
(9.64 min, 13.04 min)
C
If you really get stuck, the smaller number is before the larger. That leaves A and C.

Answer by ewatrrr(24785) (Show Source):
You can put this solution on YOUR website!

Hi Population is normally distributed. Sample n = 10 mean = 11.29 and s = 2.33 95% confidence interval: df = 9 , t = 2.262 ME = = 2.262*2.33/√10 = 1.7 11.29 - 1.7 < < 11.29 + 1.7 9.59< < 12.99 CI: ( 9.60, 13.00) Rounded to nearest tenth. As to Answers, obviously rounding off to the nearest 10th. Wish You the Best in your Studies.