13 cuz add 4 days then friday so 4×3 which is 12 and 12-25 so ye its 13
The definition of two events being mutually
exclusive (or disjoint) only means that it is not possible for the two events to
occur together. Given two events, E and F, they are mutually
exclusive and also mean independent.
In this case, since events E and F are mutually
exclusive, therefore the probability that either E or F will occur will simply
be the sum of two events.
P (E or F) = P (E) + P (F)
P (E or F) = 0.25 + 0.51
P (E or F) = 0.76
Therefore this means that there is a 76% probability that
either E or F will occur.
