1. Assume X ∼ N(20, 25),
(a) find P(X > 25)
(b) the value of x if P(X > x) = 0.975.
(c) find the values of a and b, two symmetrical values about 20
such that P(a < X < b) = 0.95.
(d) If X1, X2, . . . , X100 is random sample for the
distribution of X
• what is the sampling distribution of the sample mean X¯?
• find P(X >¯ 20.50)
(e) Suppose the...