There are 100 balls in a basket numbered 1,2...,100. 12 balls are being pulled out one after another without return. Let $X_i$ be the value on the i'th ball. Calculate $\text{Corr}(X_{11},X_{12})$
Obviously the numbers on the balls are very dependent on each other, so i don't know how to begin to calculate their expected values. Actually i don't know how to represent these variables, no known distribution comes to mind. Can anyone help?