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Question
The following is the c.d.f. of r.v. X
| x | -3 | -2 | -1 | 0 | 1 | 2 | 3 | 4 |
| F(X) | 0.1 | 0.3 | 0.5 | 0.65 | 0.75 | 0.85 | 0.9 |
*1 |
P (–1 ≤ X ≤ 2)
Solution
P (–1 ≤ X ≤ 2)
=P(X= -1) +P(X=0)+ P(X = 0)+P(X = 2)
= 0.2 + 0.15 + 0.1 + 0.1 = 0.55
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