Two coins are tossed once. Find the probability of
(i) getting 2 heads (ii) getting at least 1 head
(iii) getting no head (iv) getting 1 head and 1 tail

Answer

(1) `(3)/(4)`
(2) `(1)/(4)`

Explanation

"Let S be the sample space"
`"Then S"={"HH,HT,TH,TT"}`
`thereforen(S)=4.`
(1) Let A be the event where at least one head turns up.
`"Then A"={HH,HT,TH}`
`thereforen(A)=3.`
`Now,P(A)=(n(A))/(n(S))`
`thereforeP(A)=(3)/(4).`
(2) Let B be the event where no head turns up.
`Then B={"TT"}" "thereforen(B)=1.`
`thereforeP(B)=(n(B))/(n(S))`
`thereforeP(B)=(1)/(4).`