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    • Thread Starter

    A discrete R.V X has probability distribution:

    x -1 0 1 2 3
    a b 0.1 0.3 0.2

    E(X)= 0.95

    Find the probability X is greater than E(X)
    Find the values A and B.

    Paul plays a game in which a fair coin is spun 4 times. If the number of heads is 0 or 1 Paul loses £5. If the number of heads is 2 Paul wins £5 and if the number of heads is 3 or 4 paul wins £10.

    Show that P(W=-5) = 5/6

    Thanks for your help

    Sum of probabilities is always one...gives an equation for a and b.
    Use the formula for E(X) to form another equation for a and b.
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Updated: March 28, 2011
“Yanny” or “Laurel”
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