Binomial and Normal

The 40 yards sprint times for a soccer team are found to be normally distributed with a mean of 5.2 seconds and a standard deviation of 0.3 seconds.  What is the z-score for a player who runs a time of 5.6 seconds?

• -1.33

• 1.33

• 0.88

• 1.02

The shelf life of a particular dairy product is normally distributed with a mean of 12 days and a standard deviation of 3 days.

About what percent of the products last between 12 and 15 days?

• 68%

• 34%

• 16%

• 2.5%

The mean July daily rainfall in Hulu Kinta is 10 mm and the standard deviation is 1.5 mm

Assume that this data is normally distributed.
How many days in July (31 total days) would you expect the daily rainfall to be less than 8.5 mm?

• 5

• 6

• 7

• 10

Given a mean of 75 and a standard deviation of 7, what percentage of scores are greater than 68?

• 34%

• 84%

• 95%

• 68%

μ = 70 , σ = 8 , X = 50 . Find z score

• 2.5

• -2.5

• 5.2

• -5.2

The weights of paper discarded each week by households are normally distributed with a mean of 9.43 pounds and a standard deviation of 4.17 pounds. The top 10% of households discard at least ______ pounds of paper.

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

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%

A normally distributed random variable with a mean µ = 0 and standard deviation ơ = 1 is called a standard normal variable.

• True

• False

At Chili's, the average wait time to receive your meal is 22 minutes with a standard deviation of 9 minutes. What is the wait time for the top 12% ? Round to the nearest minute.

• 39 minutes

• 37 minutes

• 33 minutes

• 31 minutes