Answer:
→ 4.
→ 3.
→ 1.
→ 2.
Step-by-step explanation:
You need to:
Factor out 2 from , then you get the equivalent expression:
this matches with OPTION 4
Factor out 2 from , then you get the equivalent expression:
this matches with OPTION 3
Make the subtraction for , then you get the equivalent expression:
this matches with OPTION 1
Factor out 2 from , then you get the equivalent expression:
this matches with OPTION 2
Answer: The margin of error = 3.71, confidence interval = (354.04, 361.46) and it means that mean cost is lies within the confidence interval.
Step-by-step explanation:
Since we have given that
Sample size = 400
Mean = $357.75
Standard deviation = $37.89
At 95% confidence level, z = 1.96
We first find the margin of error.
Margin of error is given by
95% confidence interval would be
Hence, the margin of error = 3.71, confidence interval = (354.04, 361.46) and it means that mean cost is lies within the confidence interval.