Answer: hello your question is incomplete attached below is the complete question
answer :
a) 85.0
b) 27.4
c) (82.26, 87.74 )
Explanation:
Given data :
95% confidence interval
x ( mean ) = 85
s = 8.8
n ( sample size ) = 42
using t-distribution
a) calculate the point estimate
The point estimate = 85.0 given that a sample mean is the same as a point estimate of the sample population
b) calculate the Margin of error
df = 42 - 1 = 41
∝ = 0.05
critical value ( T ∝/2 , 41 ) = 2.02
hence ; margin of error ( E )
= 2.74 ( using margin of error calculator )
c) The 95% confidence interval
= 85 ± 2.74
(82.26, 87.74 )