Question

In: Statistics and Probability

Let X be N(µ = 16, σ^2 = 4). Graph its p.d.f. and compute the following...

Let X be N(µ = 16, σ^2 = 4). Graph its p.d.f. and compute the following quantities.

(a) Compute the probability P(X > 10).

(b) Compute the probability P(|X − 16| < 2).

(c) Compute c so that P(X ≤ c) = 0.95.

Solutions

Expert Solution

a)

                            

                             = P(Z > -3)

                             = 1 - P(Z < -3)

                             = 1 - 0.0013

                             = 0.9987

b)

                                        

                                        

                                        

                                         = P(-1 < Z < 1)

                                         = P(Z < 1) - P(Z < -1)

                                         = 0.8413 - 0.1587

                                         = 0.6826

c)

or, c = 16 + 1.645 * 2

or, c = 19.29


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