ShmoopTube

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Thank you We sneak in pure shmoop too sure brought

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to you by ball selection a really important skill If

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you plan on going into professional single college aren't there

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x number of ways to choose four balls in any

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order from a total of twenty different balls x is

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equal to the number of ways to choose blank balls

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in any order from a total of twenty different balls

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You got that read it carefully way have twenty balls

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and we're choosing for them in any order and a

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problem tells us that they're ex ember ways to do

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that But then it tells us that there's some other

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number of balls we could choose from the same set

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twenty and the number of combinations would be the same

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How is that possible But really just calls for us

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to look at this thing a little differently when we

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choose for the balls from twenty were also in a

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way choosing the other sixteen at the same time No

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it's the same in reverse Whether we choose four balls

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or sixteen you will be the same number of ways

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we can do it right way See that raised eyebrow

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Get down Here's What works using the combination formula x

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factorial over y factorial times the quantity x minus y

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factorial Nothing wake unplugging our numbers in the first example

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to get twenty factorial over four factorial times the quantity

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twenty minutes for factorial or twenty factorial over for factorial

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times sixteen factorial not right now before we do anything

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else with it Let's see what happens if we use

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sixteen balls instead of four legman who are formula And

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we get twenty factorial over sixteen factorial times the quantity

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twenty pectoral minus sixteen factorial or twenty factory over sixteen

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factorial times for factorial This thing hey check it out

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The two terms on the bottom are in different order

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but they're still getting multiplied together Yeah Same z's name 00:01:56.273 --> [endTime] Thing or answer is sixteen Bingo

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