Question

Three fair coins are tossed together. Find the probability of getting atleast one tail

Answer 1

Three fair coins are tossed together

Sample spade = {HHH, HHT, HTH, HTT, THH, THT, TTH, TTT}

n(S) = 8

Let B be the event of getting atleast one tail.

B = {HHT, HTH, HTT, THH, THT, TTH, TTT}

n(B) = 7

P(B) = `("n"("B"))/("n"("S")) = 7/8`