Probability Under the Normal Distribution

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 percentage ratings can be expected to be between 200 and 275?

• 0.4331

• 0.5671

• 0.3861

• 0.2987

Answer explanation

A standardized test has scores that can be described by a Normal model with a mean score was 100 points and a standard deviation of 10 points. What score is at the 25th percentile?

• 93.26

• 106.74

• 90.32

• 80

Answer explanation

A town's average snowfall is 48 inches per year with a standard deviation of 6 inches. Using a Normal model, what values should border the middle 50% of the model?

• 44 and 52 inches

• 42 and 54 inches

• 40 and 50 inches

• 40 and 60 inches

Answer explanation

The distances male long jumpers for State College jump are approximately normal with a mean of 263 inches and a standard deviation of 14 inches. Suppose a male long jumper's jump ranked in the 75th percentile. How long was his jump?

• 261.03 inches

• 263 inches

• 272.44 inches

• 277.25 inches

Answer explanation

Snobby University accepts only those graduate students who score in the top 5% of the GRE (Graduate Requirements Exam).

Given that µ = 151.3 and σ = 8.7, what is the lowest score you can get and still be accepted to SU? Round to the nearest whole number.

• 165

• 166

• 170

• 162

Answer explanation

What is the total area in the distribution under the curve?

• 0

• 1

• 2

• 3

It characterize the spread or range of a normal distribution/data set?

• Sample Mean

• Population Mean

• Standard Deviation

• Sample Size

Which value is found at the center of the normal curve?

• Mean

• Median

• Mode

• All of the Above

The graph of a Normal distribution is _________ to the x axis.

What case number can be applied to find P ( X > 24)?

• Case 1

• Case 2

• Case 3

• Case 4?