Question

Suppose x has a distribution with μ = 25 and σ = 22.

(a) If a random sample of size n = 40 is drawn, find μ_x, σ_x and P(25 ≤ x ≤ 27). (Round σ_x to two decimal places and the probability to four decimal places.)

μ_x =

σ_x =

P(25 ≤ x ≤ 27) =

(b) If a random sample of size n = 56 is drawn, find μ_x, σ_x and P(25 ≤ x ≤ 27). (Round σ_x to two decimal places and the probability to four decimal places.)

μ_x =

σ_x =

P(25 ≤ x ≤ 27) =

Answer 1

We have given,

a) For n=40

= 3.48

=0.7157-0.5..................................................by using normal probability table.

=0.2157

b) For n=56

  

= 2.94

=0.7517-0.5................................by using normal probability table.

=0.2517