Question

A brother and a sister are in the same math class. there are 8 boys and 10 girls in the class. one boy and one girl are randomly chosen. what is the probability that the brother and sister are chosen? write your answer as a fraction in simplest form.

Answer 1

the best one is 1/9 maybe

Answer 2

Answer:  

Hence, the probability is:

1/80

Step-by-step explanation:

A brother and a sister are in the same math class.

There are 8 boys and 10 girls in the class.

one boy and one girl are randomly chosen.

Let A be the event of choosing a sister.

and B denote the event of choosing a brother.

We have to find:

P(A∩B)

where P is the probability off an event.

As the event of choosing a brother and a sister is independent.

Hence,

P(A∩B)=P(A)×P(B).

Also P(A)=1/10

( Since out of 10 girls one girl is to be chosen).

and P(B)=1/8.

(Since out of 8 boys one boy is to be selected)

Hence,

P(A∩B)=1/8×1/10=1/80

Hence, the probability is:

1/80