Question

4.126 Wear-out of used display panels.Wear-out failure time ofelectronic components is often assumed to have a normaldistribution. Can the normal distribution be applied to thewear-out of used manufactured products, such as coloreddisplay panels? A lot of 50 used display panels was purchasedby an outlet store. Each panel displays 12 to 18 colorcharacters. Prior to the acquisition, the panels had been usedfor about one-third of their expected lifetimes. The data inthe accompanying table (saved in the file) give the failuretimes (in years) of the 50 used panels. Use the techniquesof this section to determine whether the used panel wear-outtimes are approximately normally distributed.

0.01 1.21 1.71 2.30 2.96 0.19 1.22 1.75 2.30 2.98 0.51

1.24 1.77 2.41 3.19 0.57 1.48 1.79 2.44 3.25 0.70 1.54

1.88 2.57 3.31 0.73 1.59 1.90 2.61 1.19 0.75 1.61 1.93

2.62 3.50 0.75 1.61 2.01 2.72 3.50 1.11 1.62 2.16 2.76

3.50 1.16 1.62 2.18 2.84 3.50

Short answer

The data is normally distributed.

Step-by-step solution

Given information

Here a lot of 50 display panels purchased are given.

Plotting the graph

From the above graph, it is seen that maximum data points fall in a straight line.

So, we can conclude that the data are normally distributed.