The scores of 40,000 county employees who sat for a recent civil service were normally distributed with μ = 70 and σ = 10.
The number of county employees who scored above a 90 is what?
Solution :
Given that ,
P(x > 90) = 1 - p( x< 90)
=1- p P[(x - ) / < (90 - 70) / 10]
=1- P(z < 2.00 )
= 1 - 0.9772
= 0.0228
= 40000 * 0.0228 = 912
The number of county employees = 912
The scores of 40,000 county employees who sat for a recent civil service were normally distributed...
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