Probability: Working with the standard distribution curve.

A company installs 5000 light bulbs, each with an average life of 500 hours and a standard deviation of 100 hours, and a distribution approximated by a normal curve. Find the percentage of bulbs that can be expected to last the period of time between 540 hours and 780 hours? Less than 690 hours?

Solution Summary

The standard distribution curve is used to calculate probabilities.