A bag contains 10 wool scarves, exactly one of which is red and exactly one of which is green. If Deborah reaches in and draws three scarves, simultaneously and at random, what is the probability that she selects the red scarf but not the green scarf?	Choose the correct choice: A) 3/11 B) 5/23 C) 7/30 D) 9/37 E) 11/48
Total possible ways to choose three scarves is 10C3 = 120   We need to choose the red scarf and two of 8 other scarves (not the green scarf).   The number of successful possibilities is 87/302 = 28   P(red scarf but not green scarf) = 28/120 = 7/30   The answer is 7/30.
<result>C</result>
A bag contains 10 wool scarves, exactly one of which is red and exactly one of which is green. If Deborah reaches in and draws three scarves, simultaneously and at random, what is the probability that she selects the red scarf but not the green scarf?