Answer:
The answer is : 0.0597
Step-by-step explanation:
Population mean = μ = 80
Standard deviation = σ = 20
Sample = N = 60
σ_mean = σ/√N
= (20)/√(60) = 2.582
Now we will find z1 and z2.
z1 = {(84) - μ}/σ_mean = [tex]{(84)-(80)}/(2.582)= 1.549[/tex]
z2 = {(88) - μ}/σ_mean = [tex]{(88)-(80)}/(2.582)= 3.098[/tex]
Now probability that the sample mean will be between 84 and 88 is given by:
Prob{ (1.549) ≤ Z≤ (3.098) } = (0.9990) -(0.9393) = 0.0597
