# Exam P Practice Problem 95 – Measuring Dispersion

**Problem 95-A**

The lifetime (in years) of a machine for a manufacturing plant is modeled by the random variable . The following is the density function of .

Calculate the standard deviation of the lifetime of such a machine.

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**Problem 95-B**

The travel time to work (in minutes) for an office worker has the following density function.

Calculate the variance of the travel time to work for this office worker.

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