Answer:
Given that the events A and B are mutually exclusive.
P(A) = 0.1
P(B) = 0.4
Mutually Exclusive Events: When two events are Mutually Exclusive it is impossible for them to happen together i.e
If A and B are two events then; P(A and B) = 0
then;
P(A or B) = P(A) +P(B)
By the definition of mutually exclusive events;
P(A or B) = P(A) +P(B) ......[1]
Substitute the values of P(A) = 0.1 and P(B) = 0.4 in [1] we have;
P(A or B) = P(A) +P(B) = 0.1+0.4 = 0.5