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One person speaks truth in 60% of the cases and another person in 80% of the cases. They are likely to agree in stating the same fact in

Solution

✅ Correct Option: 2

Person A tells truth in 60% of cases and lies in 40% of cases.

Person B tells truth in 80% of cases and lies in 20% of cases.

Two people will agree when both tell the truth or both lie.


Probability both tell the truth:

P(both truth)=0.60×0.80P(\text{both truth}) = 0.60 \times 0.80

P(both truth)=0.48P(\text{both truth}) = 0.48


Probability both lie:

P(both lie)=0.40×0.20P(\text{both lie}) = 0.40 \times 0.20

P(both lie)=0.08P(\text{both lie}) = 0.08


Probability they agree:

P(agree)=P(both truth)+P(both lie)P(\text{agree}) = P(\text{both truth}) + P(\text{both lie})

P(agree)=0.48+0.08P(\text{agree}) = 0.48 + 0.08

P(agree)=0.56P(\text{agree}) = 0.56

Therefore, they are likely to agree in 56% of the cases.

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