Please help me this is due in the morning and I’m not very good at fractions (number two btw)
2 answers:
You might be interested in
Of means multiplication
So
And then simplify the numerator ad denominator
=
And simplify the numerator and denominator again
=
And we are finally left with the answer which is
So
And then simplify the numerator ad denominator
=
And simplify the numerator and denominator again
=
And we are finally left with the answer which is
Answer:
The 98% confidence interval for the mean purchases of all customers is ($37.40, $61.74).
Step-by-step explanation:
We have that to find our level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of .
So it is z with a pvalue of , so
Now, find M as such
In which is the standard deviation of the population and n is the size of the sample.
The lower end of the interval is the mean subtracted by M. So it is 49.57 - 12.17 = $37.40.
The upper end of the interval is the mean added to M. So it is 49.57 + 12.17 = $61.74.
The 98% confidence interval for the mean purchases of all customers is ($37.40, $61.74).