Which Z values correspond to the outside 80% of the standard normal distribution?

Question

(A) -.26 < z < .26

(B) -1 < z < 1

(C) -.2533 < z < .2533

(D) -.5 < z < .5

Answer 1

0.2533 corresponds to 0.6 probability

-0.2533 corresponds to 0.4 probability

thus between -0.2533 and 0.2533 is 0.6 - 0.4 = 0.2 or 20% of the probability.

so 80% of the normal distribution is outside that interval.