A box contains 2 white balls, 3 black balls and 4 red balls. In how many ways can 3 balls be drawn from the box, if at least one black ball is to be included in the draw ?
A. 32
B. 48
C. 64
D. 96
E. None of these
Answer : C. 64
Explanation:
We may have ( 1 black and 2 non-black ) or ( 2 black and 1 non- black ) or ( 3 black ).
Required number of ways = (3C1 x 6C2) + (3C2 x 6C1) + (3C3) = 64.
