Probability distribution

Question

Complete parts​ (a) and​ (b) below.

The number of dogs per household in a small town

Dogs	0	1	2	3	4	5
Probability	0.670	0.201	0.085	0.024	0.013	0.008

Find the variance of the probability distribution.

Answer 1

I did this in excel but I cannot fit my solution spreadsheet here. First, you need to find the mean of the distribution. To do that, you multiply each possibly random variable value (0,1,2,3,4,5) by its probability and add those all together. The mean is 0.535. Then, you subtract each random variable value minus the mean (0.535) square it and multiply it by the probability. Do that for each value and add them all together and that is the variance. The standard deviation is the square root of the variance. Variance is 0.879