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The average lifetime of a school desk is 3,000 hours with a standard deviation of 582...

The average lifetime of a school desk is 3,000 hours with a standard deviation of 582 hours. What is the probability that

the average life of a random desk will be between 2,455.32 and 2,598.01 hours? The distribution of school desk

lifetimes is known to be normal.

Math   Statistics-And-Probability   
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