Q: A snow tire manufacturer believes that a typical set of snow tires lasts on average for 30,000 miles. They also believe that 95% of drivers get between 20,000 and 40,000 miles of use from the tires. What value of σ, the standard deviation, would be needed to make the information above approximately consistent with a Normal distribution model for tire wear? You should use the Empirical Rule to answer this question.
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Q: According to a snow tire manufacturer, the average lifespan of a set of snow tires is 30,000 miles. Additionally, 95% of drivers are thought to get between 20,000 and 40,000 miles out of their tires. To make the data above somewhat consistent with a normal distribution model for tire wear, what value of σ, the standard deviation, would be required? To respond to this question, you ought to apply the Empirical Rule.
- 5,000
- 20,000
- 10,000
- 3,333
Explanation: The value of σ\sigma, the standard deviation, that would be needed to make the information approximately consistent with a Normal distribution model for tire wear is 5,000 miles.
