A bag contains 2 yellow, 5 green and 2 blue balls. Two balls are drawn at random. What is the probability that none of the balls drawn is blue? Choose the most appropriate option
A) 7/12  B) 5/12  C) 3/7  D) 2/7  E) 5/7
Total number of balls = 2 + 5 + 2= 
<gadget id="calculator">2 + 5 + 2</gadget>
<output>9</output>
9   Let S be the sample space.   n(S)= Total number of ways of drawing 2 balls out of 9 = 9C2   Let E = Event of drawing 2 balls , none of them is blue.   n(E) = Number of ways of drawing 2 balls , none of them is blue   = Number of ways of drawing 2 balls from the total 7 (=9-2) balls = 7C2   (∵ There are two blue balls in the total 9 balls. Total number of non-blue balls = 9 - 2= 
<gadget id="calculator">9 - 2</gadget>
<output>7</output>
7)   P(E)= n(E)/n(S)   =7C2 / 9C2   =7/12   7/12ns- 7/12
<result>A</result>
A bag contains 2 yellow, 5 green and 2 blue balls. Two balls are drawn at random. What is the probability that none of the balls drawn is blue?