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Thank you We sneak Permutations and combinations are la shmoop

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If you've ever considered the consequences of your actions while

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you're probably interested in the concept of possible outcomes especially

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ever since you tried sneaking past that no trespassing sign

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outside the willoughby place you had better ideas today Oh

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Me there are a couple of different methods We used

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to count outcomes depending on whether or not the order

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of what we're counting on matters For example if you

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want to know how many different ways there are to

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arrange any three of those seven blouses you just shoplifted

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right As soon as one is in place in your

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closet you'll have one fewer options for the next life

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So order definitely matters or something like this would use

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permutations for the permutation formulas Written is n p k

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which is used to express the number of possible permutations

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of k objects from a set of any It can

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also be written in factorial over the quantity and minus

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k factorial This In the case of the blouses are

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in his seven number of blouses In our case three

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the number of glasses we want teo organized no playing

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into our formula We'd have seven factorial over the quantity

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seven minus three factorial or seven times six times five

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times four times three times two times one over four

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times three times two times one Well the four three

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two one all cancel leaving seven times extent five or

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two hundred ten possible permutations of three blouses hoping this

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party But what about when order doesn't matter Like what

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If you want to sell two of those dresses on

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the black market blouse market and you're deciding which due

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to take up the hangars well here the order of

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the two doesn't matter It's just a question of how

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many combinations of to you even select well we've got

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a formula for this one too and see our or

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in factorial over our factorial times the quantity and minus

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are factorial Where it's our objects from a set of

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an object r all right well we can plug again

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replacing end with seven and are with two to get

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seven factorial over To factorial times The quantity Seven minus

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two factorial or seven times six sometimes four times three

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times two times one i think all over two times

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one times five times four times three times two times

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one part We can start by canceling everything from the

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five on down the line here which leaves us with

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just seven times six over two times one which is

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forty two over two or twenty one twenty one combinations

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of two dresses you could try hock it on the

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street are always get even Just remember permutations went Order

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matters combinations When it doesn't That way you'll have plenty

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of time time all these over while you're serving your

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sentence in youth detention center Because shoplifting glasses is not 00:03:07.51 --> [endTime] way not good

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