Math
posted by Koia .
Maria is playing a game of chance at the Hibiscus festival, costing $1 for each game. In the game two fair dice are rolled and the sum of the numbers that turn up is found. If the sum is seven, then Maria wins $5. Otherwise Maria loses her money.
a) Construct Maria’s probability distribution for gaining.
b) Find her expected gain.
c) Find the standard deviation for this distribution.

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