Question
A coin is tossed two times. Find the probability of getting at most one head.
✓
Answer
The possible outcomes, if a coin is tossed 2 times is,
S = {(HH), (TT), (HT), (TH)}
$\therefore$ n(S) = 4
Let E = Event of getting atmost one head
= {(TT), (HT), (TH)}
$\therefore$ n(E) = 3
Hence, required probability $=\frac{\text{n(E)}}{\text{n(S)}}=\frac{3}{4}$
S = {(HH), (TT), (HT), (TH)}
$\therefore$ n(S) = 4
Let E = Event of getting atmost one head
= {(TT), (HT), (TH)}
$\therefore$ n(E) = 3
Hence, required probability $=\frac{\text{n(E)}}{\text{n(S)}}=\frac{3}{4}$
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
In the given figure, the sides $AB , BC$ and $CA$ of a triangle $ABC$ touch a circle with center $O$ and radius $r$ at $P , Q$ and R respectively. Prove that.
$a. AB + CQ = AC + BQ$
$b.$ area $(\Delta A B C)=\frac{1}{2}$ (perimeter of $\left.\Delta A B C\right) \times r$.
→$a. AB + CQ = AC + BQ$
$b.$ area $(\Delta A B C)=\frac{1}{2}$ (perimeter of $\left.\Delta A B C\right) \times r$.
Suba Rao started work in $1995$ at an annual salary of ₹$5000$ and received a ₹$200$ raise each year. In what year did his annual salary will reach ₹$7000$?
→If the coordinates of the mid-points of the sides of a triangle are $(3,4)(4,6)$ and $(5,7)$, find its vertices.
→Using remainder theorem, find the remainder when $p(x) = x^3 + 3x^2 - 5x + 4$ is divided by $(x - 2).$
→In $\triangle A B C, D, E$ and $F$ are midpoints of $B C, C A$ and $A B$ respectively. Prove that $\triangle F B D \sim \triangle DEF$ and $\triangle DEF \sim \triangle ABC$
→The angle of elevation of the top of a tower from a point $A$ on the ground is $30^{\circ}$. On moving a distance of $20$ metre towards the foot of the tower to a point $B$ the angle of elevation increases to $60^{\circ}$. Find the height of the tower and the distance of the tower from the point $A .$
→A well of diameter 3m is dug $14\ m$ deep. The earth taken out of it has been spread evenly all around it to a width of $4\ m$ to form an embankment. Find the height of the embankment.
→In given fig. tangents PQ and PR are drawn from an external point to a circle with centre O, such that $\angle\text{RPQ}=30^{\circ}$. A chord RS is drawn parallel to the tangent PQ.Find $\angle\text{RQS}$
→In an $A.P$., if the first term is $22$, the common difference is $-4$ and the sum to n terms is $64$, find n.
→If the point $P(x, y)$ is equidistant from the points $A(5,1)$ and $B(1,5)$, prove that $x=y$.
→