Urn A has balls numbered 1 through 8. Urn B has balls numbered 1 through 3. What is the probability that a 4 is drawn from Urn A followed by a 2 from Urn B?

A. [tex]\frac{1}{64}[/tex]
B. [tex]\frac{1}{24}[/tex]
C. [tex]\frac{11}{24}[/tex]
D. [tex]\frac{1}{12}[/tex]



Answer :

To determine the probability that a 4 is drawn from Urn A followed by a 2 from Urn B, we'll break down the problem into two independent events and calculate their respective probabilities before combining them.

1. Probability of drawing a 4 from Urn A:

Urn A contains balls numbered from 1 to 8. Therefore, there are 8 balls in total. Since only one of these balls is numbered 4, the probability [tex]\( P(A) \)[/tex] of drawing a 4 from Urn A is:
[tex]\[ P(A) = \frac{1}{8} \][/tex]

2. Probability of drawing a 2 from Urn B:

Urn B contains balls numbered from 1 to 3. Thus, there are 3 balls in total. Since only one of these balls is numbered 2, the probability [tex]\( P(B) \)[/tex] of drawing a 2 from Urn B is:
[tex]\[ P(B) = \frac{1}{3} \][/tex]

3. Combined probability of the two events:

Since the events of drawing balls from Urn A and Urn B are independent, the combined probability [tex]\( P(A \text{ and } B) \)[/tex] of both events happening (drawing a 4 from Urn A followed by a 2 from Urn B) is obtained by multiplying the individual probabilities:
[tex]\[ P(A \text{ and } B) = P(A) \times P(B) = \frac{1}{8} \times \frac{1}{3} = \frac{1}{24} \][/tex]

Therefore, the probability that a 4 is drawn from Urn A followed by a 2 from Urn B is [tex]\( \frac{1}{24} \)[/tex].

The correct answer is:
[tex]\[ \boxed{\frac{1}{24}} \][/tex]