ACT Math: How to do Permutations & Distinct Permutations - YoutubeRandom

## ACT Math: How to do Permutations & Distinct Permutations

This video goes with my book The ACT Math Guide, which is free for Amazon Prime members (\$9.99 if you don't have Prime). You can get the book at http://amzn.to/2iQNDFE or check it out on my website http://www.thetestuy.com/actbook.

In this ACT Math video, I'm going over the basics of permutations as well as distinct permutations. These questions have become more common on the ACT, and it's a topic you should know if you're trying to get a top score. Even if you aren't, you'll need to know the first half to this video, the basic permutations part.

Here's a synopsis of what you should know:

1. We use permutation when order matters. Permutations, like combinations, are the number of ways things can happen, but if order matters, the math is somewhat more involved. An example of permutations would be a race, it matters who finishes first.

2. We use factorials whenever we're finding permutations. Factorials are the "!" sign on your calculator.

3. For distinct permutations, we have to deal with repeated items, so we'll divide by the number of repeated items. In the example in the video, the letter "t" appeared twice, so we divided the factorial of the number of letters 6! by the number of t's 2!

Try and pick up this skill; you'll get a point or two out of it, and it's really not that bad.

Since I never remember to ask for it in videos, I'd love it if you liked and/or subscribed.

Good Luck,

Jacob

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