Permutations Combinations Factorials & Probability

Learn about permutations, combinations, factorials and probability in this math tutorial by Mario's Math Tutoring. We discuss the formulas as well as go through numerous examples. We discuss the multiplication counting principle as well as distinct permutations of n objects.

00:00 Intro
0:12 What is a Permutation?
3:00 Formula for nPr Permutations of n Objects Taken r at a Time
5:30 Formula for nCr Combinations of n Objects Taken r at a Time
7:00 Distinguishable Permutations of "MATH"
9:42 Word (Story) Problems
15:08 Examples with Cards
18:22 Probability Story Problem Examples
18:40 Formula for Calculating Probability

Related Videos:

How to Use Permutations and Combinations

Probability Examples with Cards

Probability vs Odds

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[JoshuaDHarvey]

Mario, I spent the majority of my Sunday watching videos on this and I have to say the biggest difference your video made, was really emphasizing the elimination of the multiplicities. That's a really important part of understanding even lightly understanding how this formula works. The ABC in your other video also really helped to visualize what was really going on. Great work and thank you!

[elizabethterrazas]

I am studying for my content exam to become certified as a math teacher. I was using a study resource but could not understand this by reading it. I came across your videos and now I am searching for all your videos that would help me. This is so helpful! When I am trying to choose between perm or combo, I ask myself "does the order matter?" just like you do in your video. Thank you

[danielkelsosmith]

You deserve my tuition. Feels like we’re using the same textbook as well because these are oddly similar to what I’ve been working through. Thank you Mario 🤝🏻

[rseesr]

The first time when i watch your channel was in grade 10, now i am going to my second year of uni, you vid are still helping me. you are the best math tutor on youtube. THanks :)

[esraamansour]

I just discovered your channel. I was searching for videos about permutations and combinations that can help me in the GRE test, really the explanations and the problems are solved in a clear way.

[cb]

THIS VIDEO SAVED MY LIFE. FINALLY A BREAKDOWN OF DIFFERENT SCENERIOS!! INSTEAD OF NON SENSE QUESTIONS! THANK YOU

[williamboucher]

Wow. You explained it so well! Thank you so much. Everything is now clearer.

[jozuatjonatsoi]

I can't thank you enough man. I'm a native Dutch speaker who studies in Russia where I had to learn this in Russian. Needless to say that it ate my brains up. So thank you so much for this elaborate English version.

[yelu]

It's very nice of you to put all these situations together for comparison! Very helpful, thanks!

[mohammedk]

Thank you! I'm doing the GRE 10 years post- any high school math class - and this has been the best explanation of permutations and combinations [as well as probability!] etc.for me

[crackersnucker]

This is so clear cut, I understand more but it's not as deep into the theory/algorithm as I want tho, one of the best explanation on youtube that I've found about this topic.

[souljacem]

Thank you so much. I'm a German student and I just discovered that studying math in Englisch works way better for me. You're doing great and meaningful work. Keep it up!

[brandonpanuco]

Thank you, I am having a hard time with my discrete math course and you are answering all the necessary questions that we students have when dealing with word problems.

[sanamadan]

I am preparing for a math exam and I came across your videos. They are so useful and clearly outline the key concepts to understand the the logic. Thank you so much!

[bunkryanna]

Very realistic video.


Just like how I come late for class, the lesson started before the video started.

[goldribbons]

THANK YOU SO MUCH FOR THIS VIDEO! I have a maths exam next week and I've been through so many videos and none explained it as well and as clearly as you have. I'm glad I found your channel. I will be binge watching a lot of your videos for the next 2 years of school

[keshavmadhavan]

This channel is probably one of the great discoveries of mine on YT

[particleonazock]

Really well explained, especially the word problems, I love how you go through them with a line of reasoning. This made it so easy to understand, as opposed to the mindless mathematical jargon I see frequently in textbooks. Thanks!

[riyamarabo]

I spent my whole Saturday trying to conceptualize all these three topics combined and everything failed until this video. I truly appreciate the simplicity of your explanations and connecting the concepts together!

[douglasspotts]

What a wonderful service you are providing. Thank you, thank you.