Suppose that,on average,electricians earn approximately µ = $54,000 per year in the United States.Assume that the distribution for electricians' yearly earnings is normally distributed and that the standard deviation is σ = $12,000 dollars.What is the probability that the average salary of four randomly selected electricians is more than $50,000 but less than $60,000?
A) 0.5899
B) 0.7486
C) 0.8413
D) 0.9048

Question

Quizplus · Accepted Answer

The probability that the average salary of four randomly selected electricians is more than $50,000 but less than $60,000 is 0.5899. This can be calculated using the normal distribution with mean µ = $54,000 and standard deviation σ = $12,000. The z-score for $50,000 is (50000 - 54000) / 12000 = -0.33, and the z-score for $60,000 is (60000 - 54000) / 12000 = 0.5. The probability that the average salary is between these two values is the area under the normal curve between z = -0.33 and z = 0.5, which is 0.5899.

Suppose That,on Average,electricians Earn Approximately µ = $54,000 Per Year