2 dice are rolled. Let X be the number on the first die, Y - on...

2 dice are rolled. Let X be the number on the first die, Y - on the second, and Z=X - Y. Find the expectation and standard deviation of Z.

Expert Solution

X\Y	1	2	3	4	5	6
1	0	-1	-2	-3	-4	-5
2	1	0	-1	-2	-3	-4
3	2	1	0	-1	-2	-3
4	3	2	1	0	-1	-2
5	4	3	2	1	0	-1
6	5	4	3	2	1	0

V(X)=5.83-0^2=5.83

So standard deviation is

orchestra answered 1 year ago

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