Two friends A and B have an equal number of d | vedclass

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

Question

(D) Let the number of daughters each friend has be $x$.Total number of daughters = $x + x = 2x$.We need to select $3$ tickets out of $2x$ daughters. T

Vedclass · Accepted Answer

$3$

Vedclass · Answer

(D) Let the number of daughters each friend has be $x$.Total number of daughters = $x + x = 2x$.We need to select $3$ tickets out of $2x$ daughters. The total number of ways to distribute $3$ tickets is ${}^{2x}C_3$.The number of ways to select $3$ tickets such that all go to the daughters of $A$ is ${}^xC_3$.The probability is given by $\frac{{}^xC_3}{{}^{2x}C_3} = \frac{1}{20}$.Expanding the combinations: $\frac{x(x-1)(x-2)}{3!} / \frac{2x(2x-1)(2x-2)}{3!} = \frac{1}{20}$.$\frac{x(x-1)(x-2)}{2x(2x-1)2(x-1)} = \frac{1}{20}$.$\frac{x-2}{4(2x-1)} = \frac{1}{20}$.$20(x-2) = 4(2x-1)$.$5(x-2) = 2x-1$.$5x - 10 = 2x - 1$.$3x = 9$.$x = 3$.

Two friends $A$ and $B$ have an equal number of daughters. There are three cinema tickets which are to be distributed among the daughters of $A$ and $B$. The probability that all the tickets go to the daughters of $A$ is $1/20$. The number of daughters each of them has is:

Similar Questions

$A$ box contains $25$ tickets numbered $1, 2, \dots, 25$. If two tickets are drawn at random,then the probability that the product of their numbers is even is:

One ticket is drawn at random out of $30$ tickets numbered from $1$ to $30.$ Find the probability that the number on the ticket is a multiple of $5$ or $7.$

One card is drawn from a pack of $52$ cards. The probability that it is a king or a diamond is

You are given the digits $2, 3, 4, 6,$ and $7$. In how many ways can you form a $3$-digit number without repetition of digits that is odd and greater than $300$?

If two balanced dice are tossed once,the probability of the event,that the sum of the integers coming on the upper sides of the two dice is $9$,is

Vedclass Test Series

Exam Paper Generator

Online Exam Module