The tread lives of the Super Titan radial tires under normal driving conditions are normally distributed with a mean of 34000 mi and a standard deviation of 1700 mi.

Question

(a) What is the probability that a tire selected at random will have a tread life of more than 35071 mi? Round your standard normal variable to two decimal places before using the table of values. (Give your answer to four decimal places.)


(b) If four new tires are installed in a car and they experience even wear, determine the probability that all four tires still have useful tread lives after 35071 mi of driving. Round your standard normal variable to two decimal places before using the table of values. (Give your answer to four decimal places.)

Answer 1

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