Solution:

It is given that

Probability that Maria will eat breakfast on any given day, which means: P(Breakfast)= 0.5

Probability that Maria will wear sweater on any given day is 4747, which means: P(sweater)=0.3

We are asked the probability that Gary eats breakfast or wear sweater on a particular day, which means we are asked the value of P(breakfast or sweater)

Now we already know, for 2 events A and B: P((A or B)=P(A)+P(B)−P(AB)

So we can write: 0.5 + 0.3 - (0.5 * 0.3)
=> on solving, 0.65.

Answer C.

P (Breakfast) = 0.5
P (Sweater) = 0.3
P (breakfast and sweater) = 0.5 * 0.3 = 0.15
P (breakfast or sweater) = 0.5 + 0.3 - 0.15 = 0.65

Hence, the correct answer is (C).

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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