00:01
So for this group, or for this problem, we know that we have a group of eight friends.
00:04
Let's call them a, b, c, d, e, f.
00:09
So one second here, that's, f would be the sixth, so g and h.
00:14
Now, let's say that a and b are the two friends who insist on sitting next to each other.
00:20
In this case, we can think of this as a set with only seven different individual objects that we need to be placing, where this first object comes in two different arrangements, either ab or ba, because those friends have to sit next to each other.
00:41
So, we know that they all want to sit in a row.
00:45
So it's going to take a total of eight different seats in order for them to all have a place to sit.
00:53
And let's see here.
00:55
So we have the eight different seats.
00:57
The first thing that we can do, or the way that we can approach this, is to first first, find where the two friends, find where a and b, are going to sit.
01:13
We have 1, 2, 3, 4, 5, 6, 7 different places where we can place the first of that group.
01:22
So, we have seven different options, because we can't place the first of the group at the eighth seat, because then that would mean that they're not sitting next to each other.
01:32
So we have seven options.
01:36
Then, we need to keep in mind that there are two different arrangements for each way that we seat a and b...