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Question
The probability distribution of a discrete r.v.X is as follows.
| x | 1 | 2 | 3 | 4 | 5 | 6 |
| P(X = x) | k | 2k | 3k | 4k | 5k | 6k |
Complete the following activity.
Solution: Since `sum"p"_"i"` = 1
P(X ≤ 4) = `square + square + square + square = square`
Solution
Since `sum"p"_"i"` = 1
k + 2k + 3k + 5k + 6k = 1
∴ 21k = 1
∴ k = `1/21`
P(X ≤ 4) = P(X = 1) + P(X = 2) + P(X = 3) + P(X = 4)
= k + 2k + 3k + 4k
= `1/21 + 2/21 + 3/21 + 4/21`
= `10/21`
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