# A speaks truth in 70% cases and B in 80%. What would be the probability of they will contradict each other?

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A speaks truth in 70% cases and B in 80% cases. What will be the probability that they will contradict each other in describing a single event?

posted May 19, 2015

## 1 Solution

for A
Pa(T)= .7 ;; probability of truth
Pa(L)= .3 ;; probability of lie

for B ,,
Pb(T)= .8
Pb(L)= .2

for contradiction probability = Pa(T)*Pb(L) + Pa(L)*Pb(T)
= .7*.2 + .3*.8

``````                                              =  .38
``````
solution May 19, 2015

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