00:01
The question tells us our shelf has nine novels, five chemistry books, and three history books.
00:06
On the probability of drawing four novels.
00:10
Well, in our first instance, we have 17 books total.
00:12
We should add these together, 9 plus 5 plus 3 to 17.
00:16
We have nine novels.
00:18
So the probability to draw the novel as our first book is just 9 over 17.
00:23
So probably the first novel is a novel.
00:25
The book is novel with 9 over 17.
00:27
All right.
00:28
Now for our second book, that book is now gone.
00:31
So we now have one less book and one less novel.
00:35
So we have 16 books now and eight our novels.
00:38
So we put these over each other again upon the probability...