In a game at an amusement park, a player can win 20 points, 25 points, or 30 points. the probability of winning these points is given in the table. points probability 20 0.6 25 x 30 y if jenny expects to win 22.5 points by playing the game once, the value of x is and the value of y is

(x, y) = (0.3, 0.1)

The sum of the probability numbers must be 1. That is, ...

... 0.6 + x + y = 1.0

The expected value must be 22.5. That is, ...

... 20·0.6 +25x +30y = 22.5

These two equations can be written as the system of equations ...

Subtracting the first of these equations from the second gives ...

... (5x +6y) -(5x +5y) = (2.1) -(2)

... y = 0.1

Putting this in the very first equation above, we have ...

... 0.6 +x +0.1 = 1.0

... x = 0.3 . . . . . . . . . subtract 0.7

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Step-by-step explanation: