A jar contains 20 red, 20 blue, 6 yellow and 4 pink balls. If two balls are to be selected at random and without replacement, approximately what is the probability both of them to be the same colour? Pick
A) 1/25
B) 1/15
C) 1/3
D) 1/2
E) 1
ok so jar contains 20 red 20 blue 6 yellow and 4 pink..   Adding the number of balls we get 50 total..   Now its a counting + probability exercise..   2 stages exist: Pick first ball then second ball..   Denominator for first ball = 50 since there are 50 balls   denominator for second ball = 49 since only 49 would remain   for each type ball i constructed probability of getting 2 of same.. I used a counting method.. first ball 20 chances blue and 2nd ball 19 chances blue and so on and so forth   Blue = (20*19)/(50*49) rounded to 400/2500   Red = (20*19)/(50*49) rounded to 400/2500   Yellow = (6*5)/(50*49) rounded to 30/2500   Pink = (4*3)/(49*50) rounded to 12/2500   Then I summed these individual probabilities to get 842/2500   This is ~1/3 as  800*3= 
<gadget id="calculator"> 800*3</gadget>
<output>2_400</output>
2400   ANS:1/3
<result>C</result>
A jar contains 20 red, 20 blue, 6 yellow and 4 pink balls. If two balls are to be selected at random and without replacement, approximately what is the probability both of them to be the same colour?