Answer:
Step-by-step explanation:
This is a question on hypothesis testing.
Population mean based on 30 year average for July was 90 with
a std deviation of 2.1
Sample of 5 shows average 93.5
To check whether sample average = population average
H0: x bar =90
Ha: x bar not equal 90(Two tailed test)
Test statistic =
=3.73
Since this lies outside the range (-1.96, 1.96) we reject null hypothesis
Hence we cannot say sample mean equals 90