iwannapassstats
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hey all, this question is really hard, need help ASAP
cheers
Nando has a gambling problem, and plays a game of chance:
She pays $1 to roll two six-sided dice (each with sides labelled 1 through 6). If she rolls a double (that is, if both dice display the same number), she wins $5. If she doesn't roll a double on her first roll, then she gets a second roll and wins $3 if she rolls a double on this second throw. If she doesn't roll a double on either throw, she wins nothing.
Let X be the random variable for the amount Nando gains from each game.
Paying $1 is important, as it changes the outcomes from $0, $3, and $5 to -$1, $2, and $4!
13. Find Nando's expected profit or loss if she plays 50 games.
(A) -$6.25. . . .(B) -$0.25. . . .(C) $0.25. . . .(D) $12.50. . . .(E) $62.50
14. Find the variance of her profit/loss if she plays ONE game [i.e., find Var(X)].
(A) 3.42. . . . ..(B) 3.85. . . . ..(C) 3.92. . . . .(D) 5.35. . . . . .(E) 5.42
cheers
Nando has a gambling problem, and plays a game of chance:
She pays $1 to roll two six-sided dice (each with sides labelled 1 through 6). If she rolls a double (that is, if both dice display the same number), she wins $5. If she doesn't roll a double on her first roll, then she gets a second roll and wins $3 if she rolls a double on this second throw. If she doesn't roll a double on either throw, she wins nothing.
Let X be the random variable for the amount Nando gains from each game.
Paying $1 is important, as it changes the outcomes from $0, $3, and $5 to -$1, $2, and $4!
13. Find Nando's expected profit or loss if she plays 50 games.
(A) -$6.25. . . .(B) -$0.25. . . .(C) $0.25. . . .(D) $12.50. . . .(E) $62.50
14. Find the variance of her profit/loss if she plays ONE game [i.e., find Var(X)].
(A) 3.42. . . . ..(B) 3.85. . . . ..(C) 3.92. . . . .(D) 5.35. . . . . .(E) 5.42
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