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Of the three independent events E(1),E(2...

Of the three independent events `E_(1),E_(2),and E_(3),` the probability that only `E_(1)` occurs is `alpha` only `E_(2)` occurs is `beta,` and only `E_(3)` occurs is `gamma.` Let the probability p that none of events `E_(1),E_(2), or E_(3)` occurs satisfy the equations `(alpha-2beta)p=alpha betaand (beta-3gamma)p=betagamma.` All the given probabilities are assumed to lie in the interval `(0,1).` Then
`("Probability of occurrence of"E_(1))/("Probability of occurence of"E_(3))=______.`

Text Solution

Verified by Experts

PLAN
For the events to be independent,
`P(E_(1)nnE_(2)nnE_(3))=P(E_(1)).P(E_(2)).P(E_(3))`
`P(E_(1)nnE_(2)nnE_(3))=P("only "E_(1)" occurs")`
`=P(E_(1)).(1-P(E_(2)))(1-P(E_(3)))`
Let x,y and z be probabilites of `E_(1),E_(2)" and "E_(3)`,respectivey.
`:." "alpha=x(1-y)(1-z)" "...(i)`
`" "beta=(1-x).y(1-z)" "...(ii)`
`" "gamma=(1-x)(1-y)z" "...(iii)`
`implies" "p=(1-x)(1-y)(1-z)" "...(iv)`
Given, `(alpha-2beta)p=alphabeta" and "(beta-3gamma)p=2betagamma" "...(v)`
From above equations, `x=2y" and "x=3z`
`:." "x=6z`
`implies" "(x)/(z)=6`
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