The lower bound of this interval is The upper bound of this

The lower bound of this interval is?

The upper bound of this interval is?

Solution

Confidence Interval
CI = x ± Z a/2 * (sd/ Sqrt(n))
Where,
x = Mean
sd = Standard Deviation
a = 1 - (Confidence Level/100)
Za/2 = Z-table value
CI = Confidence Interval
Mean(x)=101
Standard deviation( sd )=25
Sample Size(n)=64
Confidence Interval = [ 101 ± Z a/2 ( 25/ Sqrt ( 64) ) ]
= [ 101 - 1.96 * (3.125) , 101 + 1.96 * (3.125) ]
= [ 94.875,107.125 ]