The scores on a placement test given to college freshmen for the past five years are approximately normally distributed with a mean 71 and a variance a2 8 Would you still consider 2 8 to be a valid value of the variance if a random sample or 20 students who take this placement test this year obtain...

The scores on a placement test given to college freshmen for the past five years are approximately

Question:

The scores on a placement test given to college freshmen for the past five years are approximately normally distributed with a mean μ = 71 and a variance a2 = 8. Would you still consider σ2 = 8 to be a valid value of the variance if a random sample or 20 students who take this placement test this year obtain a value of s2 = 20?