Answer:
b
Step-by-step explanation:
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
9514 1404 393
Answer:
(c) x = -7
Step-by-step explanation:
An angle is equal to the sum of the angles into which it is divided.
∠MLK = ∠MLP + ∠PLK
164° = (x +31)° +(x +147)°
164 = 2x +178 . . . . . . collect terms
-14 = 2x . . . . . . . . . . . subtract 178
-7 = x . . . . . . . . . . . . . divide by 2