OpenStudy (anonymous):

In how many ways can 3 balls be selected from a box containing 2 red, 3 blue, 4 white and 5 black balls such that at least two selected balls are of the same colour? It is known that all the balls of a colour are identical.

5 years ago
OpenStudy (slaaibak):

Eish. Draw three cases: 2 Red + one other color 2 Blue + one other color 2 Black + one other color. Solve each individual one and add the ways together.

5 years ago
OpenStudy (slaaibak):

I seemed to have missed something. 2 Red + one any color (including red) 2 Blue + one any color (including blue) 2 Black + one any color (including black)

5 years ago