Question

A company advertises a mean lifespan of 1000 hours for a particular type of light bulb. If you were in charge of quality control at the​ factory, would you prefer that the standard deviation of the lifespans for the light bulbs be 5 hours or 50​ hours? Why?

Answer 1

I would prefer that the standard deviation of the lifespans for the light bulbs be 5 hours.

Step-by-step explanation:

Standard Deviation is the square root of the sum of square of the distance of an observation from the mean. It is used to check the dispersion (scatter) in data.

Further, If Standard Deviation is 50 hours then the life of the bulb can be like 950 hours or 1050 hours. And if Standard Deviation is 5 hours then the life of the bulb can be like 995 hours or 1005 hours.

So there is a huge variation in the life of bulb if Standard Deviation is 50 hours.

Thus, I would prefer that the standard deviation of the lifespans for the light bulbs be 5 hours.