One packet contains 2 black, 3 white and 2 red rubbers. 2 rubbers are drawn at random. What is the probability that none of the rubbers drawn is red?	Choose the correct option
A) 10/21  B) 21/23  C) 23/25  D) 21/20  E) None
Total number of rubbers = (2 + 3 + 2)= 
<gadget id="calculator">(2 + 3 + 2)</gadget>
<output>7</output>
7.   Let S be the sample space.   Then, n(S)= Number of ways of drawing 2 rubbers out of 7   = 7C2 `   =	(7 x 6)   (2 x 1)   = 21.   Let E = Event of drawing 2 rubbers, none of which is blue.   n(E)	= Number of ways of drawing 2 rubbers out of (2 + 3) rubbers.   = 5C2   =	(5 x 4)   (2 x 1)   = 10.   P(E) =	n(E)	=	10/21.   n(S)   10/21
<result>A</result>
One packet contains 2 black, 3 white and 2 red rubbers. 2 rubbers are drawn at random. What is the probability that none of the rubbers drawn is red?