Question

Assume that x has a normal distribution with the specified mean and standard deviation. Find the indicated probability. (Enter a number. Round your answer to four decimal places.) μ = 22; σ = 4.2 P(x ≥ 30) =

Answer 1

Solution :

Given that,

mean = = 22

standard deviation = = 4.2

P (x 30 )

= 1 - P (x 30 )

= 1 - P ( x -  / ) ( 30 - 22 / 4.2 )

= 1 - P ( z 8 / 4.2 )

= 1 - P ( z 1.90)

Using z table

= 1 - 0.9713

= 0.0287

Probability = 0.0287