Using sibling data collected from a statistics class, a sample of number of children per family can be created that has a mean,x= 1.78 children, and a standard deviation of s = 1.48 children. The sample size of the data was n = 36 Suppose the data collected could be considered a random sample of WCU student families. Is there convincing evidence to suggest that WCU families have less children than the 2000 national average of 1.86 children per family?

Calculate the test statistic for this 1 sample z-test.