Answer:
Step-by-step explanation:
The confidence interval for the population mean x can be calculated as:
Where x' is the sample mean, s is the population standard deviation, n is the sample size and is the z-score that let a proportion of
on the right tail.
is calculated as: 100%-99%=1%
So,
Finally, replacing the values of x' by 308, s by 17, n by 15 and by 2.576, we get that the confidence interval is:
Answer:
US$ 132.45
Step-by-step explanation:
See attachment for the missing table.
Given:
Richard’s checking account balance at the beginning of the week = $57.34
<u>Richard’s account balance at the end of the week from the given table:</u>
Deposits of the week = US$ 163.75
Expenses of the week = Groceries + Credit card bill + Gas
Expenses of the week = 25.37 + 50 + 13.27
Expenses of the week = US$ 88.64
Richard’s account balance at the end of the week = Richard’s checking account balance at the beginning of the week + Deposits of the week - Expenses of the week
Replacing with the real values:
Richard’s account balance at the end of the week = 57.34 + 163.75 - 88.64
=US$ 132.4
