+4 Seven distinct pieces of candy are to be distributed among three bags. The red bag and the blue bag must each receive at least one piece of candy; the white bag may remain empty. How many arrangements are possible?
so first I put one candy in each of the red and blue bags, which was 7⋅6 choices. now we only have 5 candies left to sort so that is 35 possibilities (because for each remaining candy, they have 3 options for which bag to go into).
and in all, that would be 7⋅6⋅35=10206 which is wrong
help
