The probability that events A and B do not occur simultaneously equals one minus the probability that events A and B occur
The probability that events A and B do not occur simultaneously equals one minus the probability that events A and B occur simultaneously. Thus, P(A and B) = 1 - 0.77 = 0.23.
The probability of neither A nor B occurring equals one minus the probability of either A or B occurring.
Thus, P(A or B) = 1 - 0.38 = 0.62.
Now, P(A or B) = P(A) + P(B) - P(A and B). Therefore, P(B) = P(A or B) - P(A) + P(A and B) = 0.62 - 0.26 +
0 .23 = 0.59.

It is already known that the introduction of a new model would cannibalize sales of existing lines as mentioned by the sales director. He states that the erosion could be 20% or more. Thus, this is the most appropriate null hypothesis. Note that this would make it a one-tailed test.

Portfolio Duration = wA DA + wB DB = 0.6*6.7 + 0.4 * 3.9 = 5.58.
Percentage change = %* = -5.58 x (0.0061) = -3.4%.Note that we can only use this computation if there is a parallel change in yields for all the bonds.

CFO = 765 + 184 - 69 - 54 - 83 - 37 + 55 + 33 = 794. Gain or loss on sale of assets is CFI, not CFO.