Prob (X = 1) = ¼, Prob (X = 2) = ½, Prob (X = 3) = ¼, where Prob (X = k) is the probability that X = k, for k = 1, 2, and 3. What is the variance of X?

We can calculate the moment of second order and we got:

And we can calculate the variance like this:

And the deviation would be:

Step-by-step explanation:

For this case we have the following distribution:

X       1,       ,2,     3

P(X) 0.25,  0.5, 0.25,

We can calculate the expected value with this formula:

We can calculate the moment of second order and we got:

And we can calculate the variance like this:

And the deviation would be:

so far i think you have the right thing going for you just remember soh cah toh

step-by-step explanation:

sine over hypotenuse

cosine   equals adjacent

tangent over hypotenuse