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Bunuel
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Maria eats breakfast or wears a sweater: Breakfast + Sweater - Both

Both (independent): 0.5 * 0.3 = 0.15

Maria eats breakfast or wears a sweater: 0.5 + 0.3 - 0.15 = 0.65

Answer C
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I understand the two are independent however may I know what's the rationale of deducting the probability of co-existence?
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The option answer C is wrong.
It is given that the two events are independent, that means they are mutually exclusive.
when two events are mutually exclusive the probability of their occurring is :-
P(A or B) = P(A) + P(B)

Answer is - E
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Sweater but not breakfast = 0.5x0.7 =0.35
Breakfast, but not sweater= 0.3 x0.5= 0.15
Both sweat and breakfast = 0.5x0.3=0.15
Adding all possibilities= 0.65
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One more way here could be to calculate probability when she neither eats breakfast nor wears sweater = P(~Breakfast)*P(~Sweater) = 0.5*0.7 = 0.35

So P(she does either activity) = 1 - P(she does neither activity) = 1 - 0.35 = 0.65

IMO: C
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