Question

A box contains 2 white balls 3 black balls and 4 red balls in how many ways can three balls be drawn from yhe box if atleast one black balll is yo be drawn

Answer 1

Number of ways in which 3 balls can be drawn from the box containing 2 White, 3 Black and 4 Red balls such that at least one black ball is included in the draw

= Number of ways in which 3 balls can be drawn from the box - Number of ways in which 3 balls can be drawn from the box such that no black ball is included in the draw

= (93)−(63)