A local bank has determined that the daily balances of the ...

[ETearle]

A local bank has determined that the daily balances of the checking accounts of its customers are normally distributed with an average of 280 and a standard deviation of 20.
 a. What percentage of its customers has daily balances of more than 275?
  b. What percentage of its customers has daily balances less than 243?
  c. What percentage of its customers' balances is between 241 and 301.60?

Question 2

The proprietor of a boutique in New York wanted to determine the average age of his customers. A random sample of 25 customers revealed an average age of 28 years with a standard deviation of 10 years. Determine a 95 confidence interval estimate for the average age of all his customers. Assume the population of customer ages is normally distributed.

[Harbringer]

Answer to Question 1

a. 59.87
b. 3.22
c. 83.43

Answer to Question 2

23.872 to 32.128

[ETearle]

YES! Correct, THANKS for helping me on my review

[hollysheppard095]

Wow, this really help