Q30 of 43 Page 296

State whether the statements are True or False

The probability that a person visiting a zoo will see the giraffe is 0.72, the probability that he will see the bears is 0.84 and the probability that he will see both is 0.52.

Let E1 = Event person will see the giraffe

and E2 = Event person will see the bear


Then, we have


P(E1) = 0.72 and P(E2) = 0.84


P(person will see both giraffe and bear) = 0.52


By General Addition Rule,


P(A ⋃ B) = P(A) + P (B) – P(A ⋂ B)


⇒ P(E1⋃ E2) = P(E1) + P(E2) – P(E1⋂ E2)


= 0.72 + 0.84 – 0.52


= 1.04 ≠ 0.52


Hence, the given statement is False.


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