Let S = Science book, F = fictionsud21 wrote:
Total books on shelf = 15
The possible ways of selecting 3 books are: (1 S, 2 F), (2 S, 1 F)
Therefore, required probability = (10C1 * 5C2)/15C3 + (10C2 * 5C1)/15C3 = (10 * 10)/455 + (45 * 5)/455 = 20/91 + 45/91 = 65/91 = [spoiler]5/7[/spoiler]
The correct answer is C.
