An event is three times as likely as its complement. What is the probability of the event?

E = some event

C = complement of event E

Since the events are complementary, this means P (E) + P (C) = 1

We know that P (E) = 3*P (C) since "an event is three times as likely as its complement"

So we can replace P (E) with 3*P (C) and then isolate P (C)

P (E) + P (C) = 1

3*P (C) + P (C) = 1

4*P (C) = 1

P (C) = 1/4

The probability of the complementary event is 1/4

So the probability of the original event is 3/4 (three times 1/4)

Answer: 3/4

note: in decimal form, 3/4 = 0.75