Sylvania's quality control division is constantly monitoring various parameters related to its products. One investigation addressed the life of incandescent light bulbs (in hours). Initially, they were satisfied with examining the average length of life. However, a recent sample taken from the production floor gave them pause for thought. The data follow:

Their initial efforts indicated that the average length of life of the light bulbs was 1,440 hours.
a. Construct a box and whisker plot of these data. On this basis, draw a conclusion concerning the distribution of the population from which this sample was drawn.
b. Conduct a hypothesis test to determine if the median length of life of the light bulbs is longer than the average length of life. Use α = 0.05.

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1,00140 550 210 280 840 620,500 1.460 940 2.080 350 150 730 2.410 .060 1150 1260 .760 1250 500 560 1.210 ,440 1,770 1270 121 ,230 230 2,100 630 500