Counting Problems

This video explains how to determine the number of ways an event can occur. It uses the counting principle and combinations.
mathispower4u.y...

[@playing_dark2553]

who is watching this in 2024

[@KASTR0]

Great videos , helpful. So much for my little brain

[@danielsama421]

for the first problem why do we do have to multiply, and for the third problem why do we have to add the different combinations?

[@CreativeGreen]

I LOVE U BRO

[@chiel5133]

for the example at 8:55 could one say that this is also possible to be written as 2x6!=1440. Is this the same or is this a coincidence?

[@AlexAlex-sq9cx]

Yes. 5! The possible ways to arrange the girls, 6 possible ways to arrange the block of those 2 boys so 6! And times 2 because u can also arrange those 2 boys so yeah 2*6! Works and even makes more sense

[@chiel5133]

@@AlexAlex-sq9cx Thanks for your reaction :D

[@caesarshi9114]

9mins>2weeks lecture

[@damndanielz464]

For the last question part 2, aren't there more ways to arrange the 2 boys? e.g 1 boy at the beginning and the other one at the end?

[@dondidendi5104]

The question stated that the 2 boys should be together

[@mseeusiems]

In a row, the beginning and the end are not connected. If we were to talk about a circle, yes, it would have counted as a solution

[@subarnaahmed392]

In the first problem, in first box we can't put 0 so there must be 39x40x40 Isn't it?

[@Mathispower4u]

O is a valid first digit since we are talking about a code. For example, 012 is a valid 3 digit code.

[@dimitrijep7872]

very nice, thank you