A company installs 5000 light bulbs, each with an average life of 500 hours, standard deviation of 100
hours, and distribution approximated by a normal curve. Calculate the percentage of bulbs and total
number of light bulbs that can be expected to last the period of time indicated. Round to the nearest
hundredth for percent, if possible.
Draw the normal curve
What range of hours constitutes 96% of light bulb hours of life?
Between 300 and 700 hours
Less than 600 hours