# Answer of Q13 final exam

At this question, why I have used 52 for both trials, doesn't it be 51 for the second trial as I keep the ball out of the bowl, so the number of balls I drag from decrease by one.

Hey Omar,

Thank you for reaching out!

I am not sure I understand your question in the context of this exercise. You are referring to the problem where there are 42 black balls and 12 white ones inside a bowl, correct?

Kind regards,

365 Hristina

Yes

Hey again Omar,

You need to consider

1. the number of ways in which you can choose 1 black ball from 42,

2. the number of ways in which you can choose 1 white ball from 12,

3. and the number of ways in which you can choose 2 balls from a total of 54.

Please, refer to the explanation of the correct answer for a more in-depth solution.

Kind regards,

365 Hristina