Answer:
The probability that a randomly selected graduate will have a starting salary of $50,000 or more is 10.56%
Explanation:
The formula for calculating a z-score is:
Z=[tex]\frac{x-μ}{σ}[/tex]
Where:
x=Score in this case is $50,000
μ=Mean or average of the salary: $45,000
σ= standard deviation of $4,000.
Z=[tex]\frac{50000-45000}{4000}[/tex]
Z= 1.25
This value has an associated probability of 0.8944= 89.44%, this means 89.44% of graduates will have a starting salary of $50,000 or less.
But if we want to know the probability that the graduate has a salary of $50,000 or more, taking into account a population of 100%=1
1-0.8944= 0.1056
Which represents that 10.56% of population of graduates will earn $50,000 or more.