Probability
posted by abc .
Let X and Y be normal random variables with means 0 and 2, respectively, and variances 1 and 9, respectively. Find the following, using the standard normal table. Express your answers to an accuracy of 4 decimal places.
P(X>0.75)=
P(X≤−1.25)=
Let Z=(Y−3)/4. Find the mean and the variance of Z.
E[Z]=
var(Z)=
P(−1≤Y≤2)=

1 P(X>0.75)= 0.2266
2 P(X≤−1.25)= 0.1056
Let Z=(Y−3)/4. Find the mean and the variance of Z.
3. E[Z]= 0.25
4. var(Z)= 0.5625
5. P(−1≤Y≤2)= 0.3413