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Question
Two balls are chosen randomly from an urn containing 6 red and 8 black balls. Suppose that we win ₹ 15 for each red ball selected and we lose ₹ 10 for each black ball selected. X denotes the winning amount, then find the values of X and number of points in its inverse images
Solution
Number of red balls = 6
Number of black balls = 8
‘X’ is the random variable denotes the winning amount.
∴ The values of ‘X’ are 0, 15, 30
i.e., X(BB) = 0
X(RB) = 15 + 0 = 15
X(RR) = 15 + 15 = 30
| Value of X | 0 | 15 | 30 | Total |
| Number of elements in inverse images | 1 | 2 | 1 | 4 |
| BB | RB, BR | RR |
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