Question

A bag contains 4 blue, 5 white and 6 green balls. Two balls are drawn at random. What is the probability that one ball is white?

Answer 1

the probability of one ball is 1

Answer 2

Answer:

$\text{The probability is }\frac{12}{21}$

Step-by-step explanation:

Given that a bag contains 4 blue, 5 white and 6 green balls. Two balls are drawn at random.

we have to find the probability that one ball is white.

$Probability=\frac{\text{Number of possible outcomes}}{\text{Total number of outcomes}}$

$\text{Probability that one ball is white is}$

$\frac{^5C_1\times ^{10}C_1}{^{15}C_2}+\frac{^5C_2}{^{15}C_2}\\\\=\frac{\frac{5!}{1!4!}\times \frac{10!}{1!9!}}{\frac{15!}{2!13!}}+\frac{\frac{5!}{2!3!}}{\frac{15!}{2!13!}}=\frac{10}{21}+\frac{2}{21}=\frac{12}{21}$