Question

There are 15 students. 5 of them are boys and 10 of them are girls. If 5 students are chosen, what is the probability that 2 or them are boys?

Answer 1

`400/1001~~39.96%`.

Explanation:

There are `((15),(5))=(15!)/(5!10!)=3003` ways to choose 5 people out of 15.

There are `((5),(2))((10),(3))=(5!)/(2!3!)*(10!)/(3!7!)=1200` ways to choose 2 boys out of 5 and 3 girls out of 10.

Thus, the answer is `1200/3003=400/1001~~39.96%`.