Question

If three coins are tossed simultaneously, find the probability of the following events.

Event B: To get at least two heads.

Answer 1

Sample space,

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

∴ n(S) = 8

Let B be the event of getting at least two heads.

∴ B = {HHH, HHT, HTH, THH}

∴ n(B) = 4

∴ `P(B) = (n(B))/(n(S))`

∴ `P(B) = 4/8`

∴ `P(B) = 1/2`