Answer:
Step-by-step explanation:
n = 10
Mean, m = (32 + 24 + 30 + 34 + 28 + 23 + 31 + 33 + 27 + 25)/10
= 28.7
From the information given,
Standard deviation, s = 1.8
For a confidence level of 95%, the corresponding z value is 1.96.
We will apply the formula
Confidence interval
= mean ± z ×standard deviation/√n
It becomes
28.7 ± 1.96 × 1.8/√10
= 28.7 ± 1.12
The lower end of the confidence interval is 28.7 - 1.12 = 27.58 years
The upper end of the confidence interval is 28.7 + 1.12 = 29.82 years
