(i) exactly two heads

Possible outcome of tossing three coins are: HTT, HHT, HHH, HTH, TTT, TTH, THT, THH

Numbers of outcomes of exactly two heads are: 3

Probability of getting exactly two heads is =

Therefore Probability of getting exactly two heads is

(ii) at least two heads

Possible outcome of tossing three coins are: HTT, HHT, HHH, HTH, TTT, TTH, THT, THH

Numbers of outcomes of atleast two heads are: 4

Probability of getting atleast two heads is =

Therefore Probability of getting atleast two heads is

(iii) at least one head and one tail

Possible outcome of tossing three coins are: HTT, HHT, HHH, HTH, TTT, TTH, THT, THH

Numbers of outcomes of at least one head and one tail are: 6

Probability of getting at least one head and one tail is =

Therefore Probability of getting at least one head and one tail is

(iv) no tails

Possible outcome of tossing three coins are: HTT, HHT, HHH, HTH, TTT, TTH, THT, THH

Numbers of outcomes of no tails are: 1

Probability of getting no tails is =

Therefore Probability of getting no tails is