SOLUTION: The entrance exam scores for police academy applicants is known to be normally distributed with a mean of 85 and a standard deviation of 20. Which of the following statements is f
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Question 871714: The entrance exam scores for police academy applicants is known to be normally distributed with a mean of 85 and a standard deviation of 20. Which of the following statements is false ?
Select one:
a. There is approximately a 70% probability that one randomly selected applicant will be score less than a 75 on the entrance exam.
b. With a passing score being 65, there is approximately a 16% probability of a randomly selecting a recruit who failed the entrance exam.
c. There is approximately a 69% probability that one randomly selected applicant will score higher than 75 on the entrance exam.
d. There is less than a 20% probability that one randomly selected applicant will be score below 68 on the entrance exam. Answer by ewatrrr(24785) (Show Source):
You can put this solution on YOUR website! mean of 85 and a standard deviation of 20
a,b,c are easy eliminations
d) P(x < 68), z = -17/10 = -.85 , p(z < -1.7) = 19.77%
Below: z = 0, z = ± 1, z= ±2 , z= ±3 are plotted.
Note: z = 0 (x value the mean of ) 50% of the area under the curve is to the left and %50 to the right