You are playing a board game in which severity of a plenty is determined by rolling three dice and adding spots on the up-face. The dice are all balanced so that each face is equally likely, and the three dice fall independently.

Question

If X1, X2, and X3 are the number of spots on the up-face of the three dice, then X= X1+X2+X3.
Use this fact to find the mean μx and the standard deviation σx without finding the distribution of of X.
(Start with the distribution of each of the Xi.)

Please help me!!!! I have been working one this for over and hour and its due tomorrow.

THANKS in ADVANCE!!!!

Answer 1

See my post to MAI on tuesday, December 16.