## Online Course Discussion Forum

Hello people!

I am kind of confused on question 30b. I have a question on what is a directly using cases, also, I don’t really know what to do on 30b. Thank you so much and have a great late new year!

-Yoyo :3

Hi Yoyo! This is Derek :D

So basically try to make sure that everyone gets ONE book first. After that, determine how you would distribute the remaining books.

For each case that you find, there are a few possibilities, so you have to include all of it in your calculations.

Hope this helps!

(I have the same problem in my hw in II-B so yee :D)

Thank you Derek! The thing I still don’t understand though is what is directly using cases and how it relates to the solution (plz don’t mention the answer dough), so how can you know if it is using cases or not. Thanks again, Derek!

:3,

Yoyo

Hey Yoyo!

So directly using cases means that you have to find the possibilities that will satisfy the condition. For example, one of the cases in this problem is if you were to give one book to each of the three friends and give the remaining to just one of the three friends. This case satisfies the condition as all the friends have at least one book. Try to find the other case(s).

Hope this helps.

Thank you Derek! I understand now. Thank you so much!

:3,

Yoyo