Answer:
The probability that the cost is kept within budget or the campaign will increase sales is 0.88
Step-by-step explanation:
The probability that the cost is kept within budget (event A) or the campaign will increase sales (event B) is the union of the probability of those two events. By basic properties of probability, this is:
P(A ∪ B) = P(A) + P (B) - P(A ∩ B)
and for independent events:
P(A ∩ B) = P(A) * P(B)
So:
P(A ∪ B) = 0.80 + 0.40 - (0.80*0.40) = 1.20 - 0.32 = 0.88