Given mean is μ=∑pixi=2.3
⇒5−2−a+1+54+6b=2.3
⇒6b−a=0.9...(1)
Also ∑pi=1
⇒51+a+31+51+b=1
⇒a+b=154...(2)
Solving, we get a=101;b=61
Variance is σ2=∑pixi2−μ2
⇒σ2=51(4)+101(1)+31(9)+51(16)+61(36)−5.29
⇒σ2=7.81
⇒100σ2=781
Let X be a random variable with distribution.
| x | −2 | −1 | 3 | 4 | 6 |
| P(X=x) | 51 | a | 31 | 51 | b |
Held on 1 Sept 2021 · Verified 6 Jul 2026.
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