The standard normal curve shown below models the population distribution of a random variable. What proportion of the values in the population does not lie between the two z-scores indicated on the diagram?

z=-1.25

z=0.80

Use the z-score table in your text (or find one online). Find the proportion of the population with a z-score of 0.80 or lower--this gives the area of the shaded region as well as the left (unshaded) tail. Then find the proportion of the population with a z-score of - 1.25 or lower (this gives the area of the unshaded left tail). Subtract the two values since you don't need the left tail area, and there's your answer.

If you have a graphing calculator with a statistics package, you should be able to use it to find this answer easily