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Question
An urn contains 5 mangoes and 4 apples. Three fruits are taken at random. If the number of apples taken is a random variable, then find the values of the random variable and number of points in its inverse images
Solution
Number of mangoes = 5
Number of Apples = 4
Total number of fruits = 9
Let ‘X’ be the random variable that denotes the number of apples taken, then it takes the values 0, 1, 2, 3
X(MMM) = 0
X(AMM or MAM or MMA) = 1
X(AAM or AMA or MAA) = 2
X(AAA) = 3
| Value of the random variable | 0 | 1 | 2 | 3 | Total |
| Number of elements in inverse image | 10 | 40 | 30 | 4 | 84 |
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