Question
A bag contains red, green, and blue balls, with a total
of 16 balls. The probability of drawing two blue balls in one draw is 3/8. How many blue balls are in the bag?Solution
Let number of blue balls in the bag be βxβ.According to question;xC2/16C2 = 3/8Or, x(x β 1) = 90Or, x2 β x β 90 = 0Or, x2 β 10x + 9x β 90 = 0Or, x(x β 10) + 9(x β 10) = 0Or, (x β 10)(x + 9) = 0Or, x = 10 or x = -9 (not possible)So, number of blue balls in the bag = 10
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