A box contains 15 black and 20 white balls. W | vedclass

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

Question

(A) Total number of balls = $15 + 20 = 35$.Number of ways to select $2$ balls from $35$ is $^{35}C_2 = \frac{35 	imes 34}{2} = 595$.'At most one whit

Vedclass · Accepted Answer

$\frac{81}{119}$

Vedclass · Answer

(A) Total number of balls = $15 + 20 = 35$.Number of ways to select $2$ balls from $35$ is $^{35}C_2 = \frac{35 	imes 34}{2} = 595$.'At most one white ball' means either $0$ white balls (both black) or $1$ white ball (one black and one white).Case $1$: Both balls are black. Number of ways = $^{15}C_2 = \frac{15 	imes 14}{2} = 105$.Case $2$: One white and one black ball. Number of ways = $^{20}C_1 	imes ^{15}C_1 = 20 	imes 15 = 300$.Total favorable outcomes = $105 + 300 = 405$.Probability = $\frac{405}{595} = \frac{81}{119}$.

$A$ box contains $15$ black and $20$ white balls. What is the probability that when $2$ balls are selected,at most one is white?

Similar Questions

The probability that a contractor will get a plumbing contract is $2/3$ and the probability that he will not get an electric contract is $5/9$. If the probability of getting at least $1$ contract is $4/5$,what is the probability that he will get both?

$3$ coins are tossed. Find the probability of getting at least $1$ head and $1$ tail.

There are $4$ envelopes with addresses and $4$ corresponding letters. The probability that no letter goes into its correct envelope is:

Three identical dice are rolled. The probability that the same number will appear on each of them is:

From a class of $12$ girls and $18$ boys,two students are chosen randomly. What is the probability that both of them are girls?

Vedclass Test Series

Exam Paper Generator

Online Exam Module