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?

• 43.31%

• 56.71%

• 38.61%

• 29.87%

Tags

CCSS.HSS.ID.A.4

The lengths of human pregnancies can be described by a Normal model with a mean of 268 days and a standard deviation of 15 days. What percentage of pregnancies will last at least 300 days?

• 1.64%

• 98.36%

• 12.34%

• 56.19%

Tags

CCSS.HSS.ID.A.4

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

Tags

CCSS.HSS.ID.A.4

For a recent English exam, the mean was 73 points and the standard deviation was 9.2 points. Find the percent of scores over 85.

• 9.61%

• 90.39%

• 28.51%

• 75.31%

Tags

CCSS.HSS.ID.A.4

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

Tags

CCSS.HSS.ID.A.4

A town has a speed limit of 45 mph. If the speeds of cars traveling in the town can be described by a Normal model with a mean of 48 mph and a standard deviation of 3.5 mph, what percent of cars are exceeding the speed limit?

• 80.43%

• 19.56%

• 23.86%

• 75%

Tags

CCSS.HSS.ID.A.4

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

• 53.93%

• 46.07%

• 37.19%

• 72.34%

Tags

CCSS.HSS.ID.A.4

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

Tags

CCSS.HSS.ID.A.4

6.5 CLT:  Red blood cell counts of women are normally distributed with a mean of 4.577 and a standard deviation of 0.382.  What percentage of women have red blood cell counts in the normal range from 4.2 to 5.4?

• 82.3%
• 77.8%
• 72.6%
• 68%

Tags

CCSS.HSS.ID.A.4

In a survey of men in the United States (ages 20-29), the mean height was 69.6 inches with a standard deviation of 3.0 inches. Find the minimum height in the top 17.5% .

• 69.98 in

• 71.18 in

• 72.40 in

• 73.01 in

Tags

CCSS.HSS.ID.A.4