Sample mean: 42 Variance: 9 What’s the 99% CI for this random variable? When i use the formula 42+/- (2.58* Std deviatn/sq root n), i realize that n is missing, should i just ignore n and go with 42+/- (2.58* Std deviatn)? Thx.

42+/-(2.58*.09^2) I think?

Raised to .5

42+/-(2.58*9^.5) plus it’s pretty easy to see that 3 * 3 = 9