# A necklace is to be made from 3 red, 2 black and 2 white beads. How many possible configurations are there?

(7!)/(3!2!2!)=5040/(6xx2xx2)=210
There are 7 beads. If all the beads were unique, there'd be 7! = 5040 ways to arrange the beads.
(7!)/(3!2!2!)=5040/(6xx2xx2)=210