Question

Suppose a population of scores x is normally distributed with μ = 16 and σ = 5. Use the standard normal distribution to find the probability indicated. (Round your answer to four decimal places.)
Pr(16 ≤ x ≤ 18.6)

Answer 1

Solution :

Given that ,

mean = = 16

standard deviation = = 5

P(16 x 18.6)

P( 16 x 18.6) = P[(16 - 16 / 5) (x - ) / (18.6 - 16 / 5)]

P(16 x 18.6)  = P(0 z 0.52)

P(16 x 18.6) = P(z 0.52) - P(z 0)

P(16 x 18.6) = 0.6985 - 0.5

Probability = 0.6485