Answer:
The answer is the third option
Answer:
78.81%
Step-by-step explanation:
We are given;
Population mean; μ = 149
Sample mean; x¯ = 147.8
Sample size; n = 88
standard deviation; σ = 14
Z-score is;
z = (x¯ - μ)/(σ/√n)
Plugging in the relevant values;
z = (147.8 - 149)/(14/√88)
z = -0.804
From z-distribution table attached, we have; p = 0.21186
P(X > 147.8) = 1 - 0.21186 = 0.78814
In percentage gives; p = 78.81%
Class B has the most consistant sleep because there is less of a difference between 6.87 and 3.65 than the other classes.