Assume z is a standard normal random variable. Then P(-1.20 ≤ z ≤ 1.50) equals _____.
A) .0483
B) .3849
C) .4332
D) .8181

Question

Quizplus · Accepted Answer

The probability that z falls between -1.20 and 1.50 in a standard normal distribution can be found by looking up the values in a standard normal (Z) table or using a calculator with statistical functions. The Z table gives the area to the left of a Z score. To find P(-1.20 ≤ z ≤ 1.50), we find the area to the left of 1.50 and subtract the area to the left of -1.20. The area to the left of 1.50 is approximately 0.9332, and the area to the left of -1.20 is approximately 0.1151. Subtracting these gives 0.9332 - 0.1151 = 0.8181, which is the probability of z falling between -1.20 and 1.50.

Assume Z Is a Standard Normal Random Variable