We want to determine in how many ways a person can watch 3 different videos. This means we need to choose the first, second, and the third video, one by one. We can analyze the number of ways in which we can place each number.
Video Number
Number of Ways
1
2
3
A person wants to watch 3 different videos. This means that we can choose the first video in 3 ways.
Video Number
Number of Ways
1
3
2
3
Then we choose the second video in 3-1, or 2 ways because we do not want to watch the same video two times.
Video Number
Number of Ways
1
3
2
2
3
Next, there is only 1 remaining video which we can choose to be our third video.
Video Number
Number of Ways
1
3
2
2
3
1
According to the Fundamental Counting Principle, the number of orders in which a person can watch 3 different videos is the product of the numbers from the second column of the table.
3 * 2 * 1 = 6
There are 6 ways in which a person can watch 3 different videos.
