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

$A$ bag contains $30$ balls numbered from $1$ to $30$. One ball is drawn randomly. The probability that the number on the ball is a multiple of $5$ or $7$ is

If $\overline{E}$ and $\overline{F}$ are the complementary events of events $E$ and $F$ respectively and if $0 < P(F) < 1,$ then

The probability of a sure event is

Study the given information carefully and answer the questions that follow: $A$ basket contains $4$ red,$5$ blue and $3$ green marbles. If $2$ marbles are drawn at random,what is the probability that both are red?

$A$ speaks truth in $60$ percent of cases and $B$ speaks truth in $70$ percent of cases. The probability that they will say the same thing while describing a single event is

Vedclass Test Series

Exam Paper Generator

Online Exam Module