Statistics Algebra

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 mean number of accidents a week at a company is 6.4 with a standard deviation of 1.5.  What proportion of weeks would you expect to have more than 7 accidents?

• 0.3446

• 0.2856

• 0.4

• 0.6554

The mean number of accidents a week at a company is 6.4 with a standard deviation of 1.5.  What proportion of weeks would you expect to have less than 5 accidents?

• 0.6915

• 0.1762

• 0.8238

• -0.93

The mean number of accidents a week at a company is 6.4 with a standard deviation of 1.5.  What proportion of weeks would you expect to have between 5 and 7 accidents?

• 0.1762

• 0.8238

• 0.6554

• 0.4792

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

• 0.0869

• 0.9962

• 0.0008

• 0.1234

Find P (-1.26 < z < 3.25). 

• 0.0047

• 0.9204

• 0.8956

• 0.4981

Annual U.S. per capita orange use: μ =11.4 lb, σ = 3lb. What annual per capita use of oranges represents the 10th percentile?

• 7.56 lbs

• 13.42 lbs

• 8.29 lbs 

• 9.38 lbs

The monthly phone bills in a city are normally distributed with a mean of 30$ and a standard deviation of 12$. Find the x-value that correspond to z-scores of 3.17. 

• $1.80 

• $68.04

• $32.76

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 22%.

• 69.37 in 

• 67.58 in 

• 73.12 in 

Find the z-score that has 12.71% of the distribution’s area to its right.

• -0.06

• 1.14

• -1.41

• 1.64