Answer:
$20.84
Step-by-step explanation:
To solve the above question, we would be using the z score formula
The formula for calculating a z-score :
z = (x - μ)/σ,
where x is the raw score
μ is the population mean
σ is the population standard deviation
x = unknown
μ = $17.90
σ = $1.50
We were not given z score in the above question but this can be determined.
We are told in the question to find the amount that the highest 2.5% of the employees hourly wages is greater than.
Hence, our confidence interval = 100 - 2.5 = 97.5%
The z score for 97.5% = 1.96
Below are inequalities equations with more explanation.
P(X ≥ x) = 2.5% = 0.025
P(X ≤ x) = 1 - 0.025 = 0.975
P (X - μ)/σ ≤ (x - μ)/σ) = 0.975
z ≤ (x - μ)/σ = 0.975
z ≤ 1.96 = 0.975
z = (x - μ)/σ,
1.96 = x - 17.90/1.5
Cross Multiply
1.96 × 1.5 = x - 17.90
x = (1.96 × 1.5) + 17.90
x = 2.94 + 17.90
x = 20.84
Therefore, the amount that the highest 2.5% of the employees hourly wages is greater than is $20.84
