The teachers at a primary school have devised a particular method to teach arithmetic. They want to find out if this method produces dispersion in mean scores. In order to do so, at first, they took a sample of 25 students who were taught that particular method of arithmetic. Then their test scores were taken into consideration, assuming that the test scores of all the students in that school are approximately normally distributed. Their test score produced an average variance of 180 while the population is assumed to produce a test score of 165. Using a 95% confidence level, can you conclude that the variance of all the test scores of that primary school is different from 165?

The teachers at a primary school have devised a particular method to teach arithmetic. They want to find out if this method produces dispersion in mean scores. In order to do so, at first, they took a sample of 25 students who were taught that particular method of arithmetic. Then their test scores were taken into consideration, assuming that the test scores of all the students in that school are approximately normally distributed. Their test score produced an average variance of 180 while the population is assumed to produce a test score of 165.

Using a 95% confidence level, can you conclude that the variance of all the test scores of that primary school is different from 165?