In a simultaneous toss of two coins, find the probability of getting:

(i) exactly one head, (ii) at most one head

The sample space is,

S = {HH, TT, HT, TH}

Total events, n(S) = 4

(i). To find the probability of getting exactly one head, we need to find the events when exactly one head occurs.

Events when exactly one head occurs,

s₁ = {HT, TH}

n(s₁) = 2

Thus, probability of getting exactly one head, P(exactly one head) =

⇒ P(exactly one head) =

(ii). To find the probability of getting atmost one head, we need to find the events when atmost one head occurs.

So, events when atmost one head occurs,

s₂ = {HT, TH, TT}

n(s₂) = 3

Thus, probability of getting atmost one head, P(atmost one head) =

⇒ P(atmost one head) =