A coin is tossed n times. The probability of | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) The probability of getting a head in a single toss is $p = \frac{1}{2}$,and the probability of getting a tail is $q = 1 - p = \frac{1}{2}$.The pro

Vedclass · Accepted Answer

$3$

Vedclass · Answer

(B) The probability of getting a head in a single toss is $p = \frac{1}{2}$,and the probability of getting a tail is $q = 1 - p = \frac{1}{2}$.The probability of getting no heads in $n$ tosses is $P(	ext{no head}) = q^n = (\frac{1}{2})^n$.The probability of getting at least one head is $P(	ext{at least one head}) = 1 - P(	ext{no head}) = 1 - (\frac{1}{2})^n$.Given that $1 - (\frac{1}{2})^n > 0.8$,we have:$1 - 0.8 > (\frac{1}{2})^n$$0.2 > (\frac{1}{2})^n$$\frac{1}{5} > \frac{1}{2^n}$$2^n > 5$.For $n = 2$,$2^2 = 4 For $n = 3$,$2^3 = 8 > 5$.Thus,the least value of $n$ is $3$.

$A$ coin is tossed $n$ times. The probability of getting a head at least once is greater than $0.8$. Then,the least value of such $n$ is:

Similar Questions

If light of wavelength $\lambda_1$ is allowed to fall on a metal,then the kinetic energy of the photoelectrons emitted is $E_1$. If the wavelength of light changes to $\lambda_2$,then the kinetic energy of the electrons changes to $E_2$. Then the work function of the metal is:

If a body is projected with an angle $\theta$ to the horizontal,then

Which zone of the blast furnace has the highest temperature?

When a spring is stretched by $2 \ cm$,it stores $100 \ J$ of energy. If it is further stretched by $2 \ cm$,the stored energy will be increased by $.... \ J$.

Heat energy is incident on the surface at the rate of $1000 ~J/min$. If the coefficient of absorption is $0.8$ and the coefficient of reflection is $0.1$,then the heat energy transmitted by the surface in $5$ minutes is: (in $~J$)

Vedclass Test Series

Exam Paper Generator

Online Exam Module