Answer:
a) 0.8413
b) 421
c)
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = 165
Standard Deviation, σ = 15
We are given that the distribution of IQ examination scores is a bell shaped distribution that is a normal distribution.
Formula:
a) P(IQ scores at most 180)
P(x < 180)
Calculation the value from standard normal z table, we have,
b) Number of the members of the club have IQ scores at most 180
n = 500
c) P(X< x) = 0.95
We have to find the value of x such that the probability is 0.95
Calculation the value from standard normal z table, we have,