Costco installs automobile tires on a first-come first-serve basis. the total time a customer needs to wait for the installation to be completed follows the normal distribution with a mean time of 106.3 minutes and a standard deviation of 18.5 minutes. what is the probability that a randomly selected customer will wait between 80 and 95 minutes for his or her tires to be installed?

Question

Gianna Anderson

Mathematics

29 July, 22:00

Costco installs automobile tires on a first-come first-serve basis. the total time a customer needs to wait for the installation to be completed follows the normal distribution with a mean time of 106.3 minutes and a standard deviation of 18.5 minutes. what is the probability that a randomly selected customer will wait between 80 and 95 minutes for his or her tires to be installed?

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Answers (1)

Know the Answer?

Kenyon Kerr · Answer 1

Given:

μ =106.3 minutes

σ =18.5 minutes

Need to find

P (80
P (x) = Z ((95-μ ) / σ ) - Z ((80-μ ) / σ )

=Z (-0.61081) - Z (-1.42162)

=0.27066-0.077568

=0.1931

Therefore probability of customers waiting between 80 and 95 minutes is 0.1931