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Given the probability of happening an event A is 0.80 and event B is 0.60.

Col A: The Probability of happening event A or B

Col B: 0.92

a)Col A is Greater.

b)Col B is Greater.

c)Both Col's are equal.

d)Answer cannot be determined from the information given.

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Let P(A)= Probability of A happening = 0.80 ; P(B)= Probability of B happening = 0.60;

P(A')= Probability of A NOT happening = 0.20 ; P(B')= Probability of B NOT happening = 0.40;

Solution 1: P(A)P(B') + P(A')P(B) + P(A')P(B') = 0.8*0.4+0.2*0.6+0.8*0.6 = 0.32+0.12+0.48

=0.92. So on this basis, the answer is "C".

Solution 2: Prob that either A or B happens is 1 minus probability that neither happens. So

Prob = 1 - (0.20*0.40) = 0.20. So on this basis, the answer is "B".

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Please Clarify which line of reasoning and hence the solution is correct.