According to the World Health Organization, the average height of a one-year-old child is 29”. You believe children with a particular disease are smaller than average, so you draw a sample of 20 children with this disease and find a mean height of 27.5" and a sample standard deviation of 1.5”.
The test statistic is –4.4721 and the p-value is 0.00013 using the calculator function TTEST.
If =0.05, what conclusions can be made?