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प्रश्न
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 (X ≤ 3/ X > 0)
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उत्तर
(X ≤ 3) ∩ (X > 0)
= {−3, −2, −1, 0, 1, 2, 3} ∩ {1, 2, 3, 4}
= {1, 2, 3}
∴ P[(X ≤ 3) ∩ ( X > 0)]
= P(X = 1)+ P(X = 2)+ P(X = 3)
∴ P[(X ≤ 3) / ( X > 0)]
= `(P[(X ≤ 3) ∩ ( X > 0)])/(P(X > 0))`
= `(P(X = 1) + P(X = 2) + P(X=3))/(P(X = 1) + P(X = 2) + P(X = 3) + P(X = 4))`
= `(0.1 + 0.1 + 0.05)/(0.1 + 0.1 + 0.05 + 0.1)`
=`0.25/0.35`
= `5/7`
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