Answer:
Answer is .
Step-by-step explanation:
Total teens = 28
12 teenagers, in total, had a sister
7 teenagers, in total, had a brother
3 teenagers had both a sister and brother.
To get the required probability, we will consider the following two details:
3 teenagers have both a brother and sister and 12 have a sister.
Therefore, the probability that a randomly selected teenager who has a sister also has a brother will be =
Answer is .