The Best Shop
Three shops sell light bulb. A sample of 100 light bulbs is taken from each shop and the working life of each is measured in hours. The following table shows The mean time and the range for each shop:
Which shop you recommend to someone who is looking to buy a new light bulb?
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1 solution
Recommending shops A or C is the best option, because even though they have a lower hour mean than B, it has half the range. Since shop B has a large range, there are many bulbs that ended up having a shorter life than A or C would. Since both A and C have the same range, and C has a higher mean, C is the shop to recommend.