Question

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.

Answer 1

best website for this type of problem

http://davidmlane.com/hyperstat/z_table.html

just enter the data

Answer 2

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