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 = 18; σ = 3.4

P(x ≥ 30) =

Answer 1

Solution :

Given that,

mean = = 18

P (x 30 )

= 1 - P (x 30 )

= 1 - P ( x -  / ) ( 30 - 18 / 3.4 )

= 1 - P ( z 12 / 3.4 )

= 1 - P ( z 3.53 )

Using z table

= 1 - 0.9998

= 0.0002

Probability = 0.0002