Given X ~ N(12,64)

Question

I have no idea how to figure this one out. Please help! thanks

x has a ____________ Distribution 


µ=______          s2_________          s=__________


P(X > 12)  =  ______

 
the 50th %ile is equal to what number?

Answer 1

Andrew,

            This is the notation that tell you that the random variable X has been chosen from a normal distribution with a mean of 12 and a variance of 64. Since the variance is 64 what is the standard deviation (s²=64).

Since we are dealing with a normal distribution which is symmetric about the mean, the probability that X>12 i.e.P(X>12)=.5

 

Hope this helps

 

Jim