The probability of an event P happening is (frac{1}{5}) and that of event Q is (frac{1}{4}). If the events are independent, what is the probability that neither of them happens?
-
A.
(frac{4}{5}) -
B.
(frac{3}{4}) -
C.
(frac{3}{5}) -
D.
(frac{1}{20})
Correct Answer: Option C
Explanation
prob(p) = (frac{1}{5})
prob(Q) = (frac{1}{4})
Prob(neither p) = 1 – (frac{1}{5})
(frac{5 – 1}{5} = frac{4}{5})
prob(neither Q) = 1 – (frac{1}{4})
(frac{4 – 1}{4} = frac{3}{4})
prob(neither of them) = (frac{4}{5} times frac{3}{4} = frac{12}{20})
= (frac{3}{5})