Question

A sample of 500 evening students revealed that their annual incomes were normally distributed with a mean income of $30,000 and a standard deviation of $3,000. What is the income that separates the bottom 5% from the top 95% of the incomes?

Answer 1

Hello Sir/ Mam

Given that:

Mean =	30000.00
Standard Deviation =	3,000.00

Hence,

For top 5%, z-score = 1.645, hence,

X = (1.645*3000) + 30000 = 34935

For bottom 5%, z-score = 1-.645, hence,

X = (-1.645*3000) + 30000 = 25065

I hope this clear your doubt.

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