Answer:
Sample size = 1
Not a reasonable sample size
Step-by-step explanation:
Mean of the test scores = u = 100
Standard deviation of the test scores = σ = 12
Confidence Level = 90%
The z-score for 90% confidence level = z = 1.645
Mean IQ should be 33 points within the sample mean. So,
Error size = E = 33
Sample size = n ?
Since the distribution is normal, we can use the formula of margin of error for z-distribution to calculate the missing sample size.
Using the given values, we get:
Rounding to the next bigger integer the sample size comes out to be 1. This is not a reasonable estimate for a real world calculation as we cannot draw a conclusion for a complete population based on the sample size of 1 person