- #1

CAH

- 48

- 0

Member warned multiple times about not using the homework template

**See the photo of the question+ mark scheme!**

I don't understand a question on finding an expression for the variance of something...

I don't understand a question on finding an expression for the variance of something...

Attempt at solution: also I worked out c as (3/2) previously, which is correct

Var(U) = (3/2)^2 x Var(Xbar) = 9/4n^2 x a^2/18

I'll attach a photo of this too if it's easier to read, my problem is that I thought var(Xbar) = var(x/n) = 1/n^2 x var(x)

... But they have done var(Xbar) = 1/n x var(x) ...?