It is well known that IQ is distributed approximately normal

It is well known that IQ is distributed approximately normally in the US population with a mean of 100 and a standard deviation of 16. A study is done of a retirement community in Florida with a sample size of 4,000. The researcher hypothesizes that the mean IQ in this community is higher than the expected US average of 100. What statistical test should s/he use to test this hypothesis?

A) One sample t test
B) One sample Z test
C) Independent samples t test
D) Analysis of Variance

Solution

B) One sample Z test can be used since population is normal, and standard deviation is also known.