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