Question

If you select a random z-score from the normal distribution, what is the probability that you will get a value greater than 2.5? Put differently, P(z>1.5) = ? (Answer to 3 digits after the decimal.) ?

Answer 1

Solution:

P(Z > 2.5) = 1 - P(Z < 2.50) = 1 - 0.9938 = 0.0062 = 0.006

P(Z > 2.5) = 0.006

(Use z table to find P(Z < 2.50) .See the column of z in the z table. See 2.5 in this column. and then see the corresponding value in the row at .00

)

Now ,

P(Z > 1.5) = 1 - P(Z < 1.50) = 1 - 0.9332 = 0.067

P(Z > 1.50) = 0.067

(Use z table to find P(Z < 1.50) .See the column of z in the z table. See 1.5 in this column. and then see the corresponding value in the row at .00

)