Given:
n = 27, sample size
df = n-1 = 26, degrees of freedom
xb = 11.8, sample mean
s = 2.3, sample standard deviation.
Because population statistics are not known, we should use the Student's t-distribution.
At 99% confidence interval, the t-value = 2.779 (from tables).
The confidence interval is
11.8 +/- 2.779*(2.3/√(27)) = 11.8 +/- 1.23 = (10.57, 13.03)
Answer: (10.6, 13.0) to the nearest tenth
9c + 8 - 2c + -4
like terms
9c - 2c +8 +-4
7c + 4
Answer:
1. at 1 hour, 3 miles is the distance.
2. at 0 hours, 0 miles is the distance.
3. at 3 hours, 9 miles is the distance.
Hope this helps!
1. 6
2. 64