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7. Professors’ Salaries The average salary for a Queens
College full professor is $85,900. If the average salaries
are normally distributed with a standard deviation of
$11,000, find these probabilities. a. 0.3557 (TI: 0.3547)
a. The professor makes more than $90,000.
b. The professor makes more than $75,000.
Source: AAUP, Chronicle of Higher Education.
2 answers
a. Find the Z score
z score = (X value - the mean)/ Standard Deviation
(90,000 - 85,900)/11,000 = .372
Then find the probability of the Z score happening
P(Z > .372)
Note: Find the probability using a TI- 83/84 calculator.
Keys: 2nd, Vars, Normalcdf (Lower:.372 Upper: 10,000)
Final answer: .354
z score = (X value - the mean)/ Standard Deviation
(90,000 - 85,900)/11,000 = .372
Then find the probability of the Z score happening
P(Z > .372)
Note: Find the probability using a TI- 83/84 calculator.
Keys: 2nd, Vars, Normalcdf (Lower:.372 Upper: 10,000)
Final answer: .354