Question

In: Statistics and Probability

A.) A telephone manufacturer finds that the life spans of its telephones are normally distributed, with...

A.) A telephone manufacturer finds that the life spans of its telephones are normally distributed, with a mean of 6.7 years and a standard deviation of 0.5 year. (Round your answers to three decimal places.)

What percent of its telephones will last at least 7.25 years?

What percent of its telephones will last between 5.8 years and 6.8 years?

What percent of its telephones will last less than 6.9 years?

B.) The amount of time customers spend waiting in line at the ticket counter of an amusement park is normally distributed, with a mean of 6.5 min and a standard deviation of 1 min.

Find the z-score for the following data value 8 min.

Find the probability that a customer will wait less than 8 minutes. (Round your answer to three decimal places.)

Find the z-score for the following data value 6 min.

Find the probability that a customer will wait less than 6 minutes. (Round your answer to three decimal places.)

Expert Solution

B)

thank you.

orchestra answered 1 year ago

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