Probability Under the Normal Distribution

A town's average snowfall is 48 inches per year with a standard deviation of 6 inches. Using a Normal model, what percent of snowfall amounts will be between 40 and 50?

• 0.5393

• 0.4607

• 0.3719

• 0.7234

A bank's loan officer rates applicants for credit. The ratings can be described by a Normal model with a mean of 200 and a standard deviation of 50. What is the rating which cuts off the bottom 20%?

• 157.92

• 242.08

• 189.34

• 190.60

Find the area under the standard normal curve to the right of z = -2.67.

• 0.0869

• 0.9962

• 0.0008

• 0.1234

This data is normally distributed.  What percent of the data is in the shaded region?

• 68%

• 95%

• 99.7%

• 50%

This data is normally distributed.  What percent of the data is in the shaded region?

• 68%

• 32%

• 95%

• 50%

What is the total area under the normal curve in a standard normal distribution?

• 1

• 2

• 3

• 4

Where can we locate the mean in the normal curve?

• to the left portion

• to the right portion

• at the center

• on the z - axis

Find the area under the normal distribution curve to the left of 
Z=0.27.

• 0.3936

• 0.3897

• 0.6064

• 0.4892

Find the area under the normal distribution curve between a z=-1.26 and z=.57. 

• 0.0047

• 0.9204

• 0.6119

• 0.4981

Find the area of the shaded region if the z-score is 0.75

• 0.2266

• 0.7734

• 0.758

• 0.242