Question

For a normal population with µ = 100 and σ = 20:

1. What is the probability of a particular score being greater than 110?

2. What is the probability of a particular score being less than 50?

Answer 1

Use z-scores:

z = (x - mean)/sd

Your data:
x = 110, 50
mean = 100
sd = 20

Calculate both z-scores. Use a z-table to determine probability for each score.

I hope this will help get you started.