Complete Question
The complete question is shown on the first uploaded image
Answer:
a
b
c
Generally the width at n = 49 is mathematically represented as
Generally the width at n = 196 is mathematically represented as
d
The correct option is E
Step-by-step explanation:
From the question we are told that
The sample mean is
The standard deviation is
Generally given that the confidence level is 95% then the level of significance is
=>
Generally from the normal distribution table the critical value of is
Considering question a
From the question n = 49
Generally the margin of error is mathematically represented as
=>
=>
Generally 95% confidence interval is mathematically represented as
=>
Considering question b
From the question n = 196
Generally the margin of error is mathematically represented as
=>
=>
Generally 95% confidence interval is mathematically represented as
=>
Considering question c
Generally the width at n = 49 is mathematically represented as
Generally the width at n = 196 is mathematically represented as
Now when the sample size is quadrupled i.e from n = 49 to n = 196
The width of the confidence interval decrease by 2 from 1.904 to 0.9374