The Tread Lives of Super Titan Radial Tires Under Normal

Short Answer

The tread lives of Super Titan radial tires under normal driving conditions are normally distributed with a mean of 42,000 mi and a standard deviation of 5,000 mi. What is the probability that a tire selected at random will have a tread life of more than 35,000 mi? Round your answer to four decimal places, if necessary.
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If four new tires are installed on a car and they experience even wear, determine the probability that all four tires still have useful tread lives after 35,000 mi of driving. Round your answer to four decimal places, if necessary.
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