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Let B_i(i=1,2,3) be three independent events in a sample space. The probability that only B_1 occur is α , only B_2 occurs is β and only B_3 occurs…

JEE Main 2021 — Mathematics Probability & Statistics

2021integerhard

Let Bi(i=1,2,3){B}_{i}(i=1,2,3)Bi​(i=1,2,3) be three independent events in a sample space. The probability that only B1{B}_{1}B1​ occur is α,\alpha ,α, only B2{B}_{2}B2​ occurs is β\betaβ and only B3{B}_{3}B3​ occurs is γ.\gamma .γ. Let ppp be the probability that none of the events Bi{B}_{i}Bi​ occurs and these 444 probabilities satisfy the equations (α−2β)p=αβ(\alpha -2\beta )p=\alpha \beta(α−2β)p=αβ and (β−3γ)p=2βγ(\beta -3\gamma )p=2\beta \gamma(β−3γ)p=2βγ (All the probabilities are assumed to lie in the interval (0,1))(0,1))(0,1)) Then P(B1)P(B3)\frac{P({B}_{1})}{P({B}_{3})}P(B3​)P(B1​)​ is equal to______.

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Held on 24 Feb 2021 · Verified 6 Jul 2026.

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