For groups of 15 randomly selected people the mean number of

For groups of 15 randomly selected people, the mean number of people that are taking a statistics course is µ=12.75 people, and the standard deviation is = 0.8 people.

a. Determine the mean and standard deviation and explain what they mean in a complete sentence.

b. Using the range rule of thumb, determine the maximum and minimum unusual values and explain what they mean in a complete sentence. SHOW WORK!!!

Solution

a)

mean = 17.75

sigma = 0.8 / srqt (15) = 0.2066

The standard deviation measures how concentrated the data are around the mean; the more concentrated, the smaller the standard deviation.

A small standard deviation can be a goal in certain situations where the results are restricted, for example, in product manufacturing and quality control. A particular type of car part that has to be 2 centimeters in diameter to fit properly had better not have a very big standard deviation during the manufacturing process. A big standard deviation in this case would mean that lots of parts end up in the trash because they don’t fit right; either that or the cars will have problems down the road.

the mean is like all of values can take that value but there are not that value

b)

I can gladly help you but you should post it in a new question