the average single smart phone cell phone bill is now averaging $73 with a standard deviation...

the average single smart phone cell phone bill is now averaging $73 with a standard deviation of $20.

a. what is the probability that a random person will have a bill more than $70?

b. what is the probability that a sample mean of 40 produces a sample mean less than $73?

c. what is the probability that a sample mean of 40 produces a sample mean more than $75?

Expert Solution

population mean=73

population standard deviation=20

orchestra answered 1 year ago

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