Answer:
0.0618
Step-by-step explanation:
z = (x - μ)/σ, where
x is the raw score = 69
μ is the sample mean = population mean = 65
σ is the sample standard deviation
This is calculated as:
= Population standard deviation/√n
Where n = number of samples = 25
σ = 13/√25
σ = 13/5 = 2.6
Sample standard deviation = 2.6
z = (69 - 65) / 2.6
z = 4/2.6
z = 1.53846
Approximately to 2 decimal places = 1.54
Using the z score table to determine the probability,
P(x = 69) = P(z = 1.54)
= 0.93822.
The probability that the sample mean is greater than 69 is
P(x>Z) = 1 - 0.93822
P(x>Z) = 0.06178
Approximately to 4 decimal places = 0.0618
