Answer :
Given:
μ = 9.9 hours, population mean
σ = 4.54 hours, population standard deviation
For the random variable x = 3 hours, the z-score is
z = (3 - 9.92)/4.54 = -1.5242
From standard tables, obtain
P(x ≤ 3) = 0.064 = 6.4%
Answer: 6.4% on both tails of the normal distribution
μ = 9.9 hours, population mean
σ = 4.54 hours, population standard deviation
For the random variable x = 3 hours, the z-score is
z = (3 - 9.92)/4.54 = -1.5242
From standard tables, obtain
P(x ≤ 3) = 0.064 = 6.4%
Answer: 6.4% on both tails of the normal distribution
