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An election ballot asks voters to select six city commissioners from a group of twenty candidates. In how many ways can this be done?Six city commissioners can be selected from a group of twenty candidates indifferent waysHelp Me Solve ThisView an ExampleGet More HelpClear All

User Aleksei Tirman
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1 Answer

19 votes
19 votes

we were given 20 candidates

to select 6 city commisioners

this is a combination question

this means 20C6

so using combination formular

nCr = n!/(n-r)! r!

n = 20

r = 6

nCr = 20!/(20-6)! 6!

nCr = 20!/14! 6!

nCr = 20 x 19 x 18 x 17 x 16 x 15 x 14!/14! 6!

nCr = 155040

the selection can be done in 155040 ways

User Intelfx
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