Counting

 

A baking club wants to form an executive committee. There are $20$ people in the baking club, including Mark. In how many ways can the baking club form an executive committee with $7$ people, including Mark?     

 

₂₀C₇ = 77,520    

 

This is called the combination of 20 items taken 7 at a time.    

Sometimes called the shortened form of "20 choose 7" but    

I prefer the first way.   

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