Find solutions to your problems with the expert advice available on IDNLearn.com. Discover the information you need from our experienced professionals who provide accurate and reliable answers to all your questions.

The probability of drawing two white balls from a jar at random without replacement is [tex]\frac{1}{5}[/tex].

The probability of drawing a white ball first is [tex]\frac{7}{15}[/tex].

What is the probability of drawing a second white ball, given that the first ball drawn was white?

A. [tex]\frac{2}{3}[/tex]
B. [tex]\frac{7}{75}[/tex]
C. [tex]\frac{3}{7}[/tex]
D. [tex]\frac{4}{15}[/tex]


Sagot :

To find the probability of drawing a second white ball given that the first ball drawn was white, we will use conditional probability. This problem can be framed as finding [tex]\( P(B|A) \)[/tex], where:

- [tex]\( A \)[/tex] is the event of drawing a white ball first.
- [tex]\( B \)[/tex] is the event of drawing a white ball second.

We need to find [tex]\( P(B|A) \)[/tex], which is the conditional probability of [tex]\( B \)[/tex] given [tex]\( A \)[/tex]. According to the formula for conditional probability:

[tex]\[ P(B|A) = \frac{P(A \text{ and } B)}{P(A)} \][/tex]

We have the following information provided in the problem:

- [tex]\( P(A \text{ and } B) = \frac{1}{5} \)[/tex] (the probability of drawing two white balls consecutively).
- [tex]\( P(A) = \frac{7}{15} \)[/tex] (the probability of drawing a white ball first).

Now, substituting these values into the formula for conditional probability:

[tex]\[ P(B|A) = \frac{\frac{1}{5}}{\frac{7}{15}} \][/tex]

This simplifies to:

[tex]\[ P(B|A) = \frac{1/5}{7/15} = \frac{1/5 \times 15/7}{1} = \frac{15}{35} = \frac{3}{7} \][/tex]

Hence, the probability of drawing a second white ball given that the first ball drawn was white is [tex]\(\frac{3}{7}\)[/tex].

Therefore, the correct answer is [tex]\(\frac{3}{7}\)[/tex].
Thank you for using this platform to share and learn. Don't hesitate to keep asking and answering. We value every contribution you make. For dependable answers, trust IDNLearn.com. Thank you for visiting, and we look forward to assisting you again.