Statistics: an appliance on a bell curve

Tutoring statistics, everyday examples are useful. The tutor mentions a hypothetical with an appliance.

The following is according to my understanding.

Let’s imagine someone has an appliance that is four years old. Let’s imagine said appliance develops a problem that needs to be fixed or it can’t work.

Now, let’s imagine the appliance owner looks up how long said appliance typically works, and discovers it’s eight to twelve years.

In simple terms, that just as likely indicates that the mean (average, if you prefer) age it lasts is eight years, with 95 percent lasting until twelve years. That’s a common way the bell curve, aka the normal distribution, is applied. Moreover, the bell curve is symmetrical, suggesting that only about five percent of those appliances last four or less years.

Therefore, my read of the situation is that if said person’s appliance needs a repair at four years that isn’t major, it’s just as likely worth doing, since it’s likely they can look forward to at least another four years of use after said repair.

However, this is all hypothetical, just serving as an example about the normal distribution.

Source:

Harnett, D.L., Murphy, J.L. (1993). Statistical Analysis for Business and Economics, first Canadian edition. Addison-Wesley Publishers Limited.

Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.