Question
In a basket, there are (x + 7) red balls, ‘x’ blue balls, and (x + 3) black balls. If the probability of picking two blue balls at random is (1/28), then find the value of ‘x’.
Solution
According to the question, Total number of balls in the basket = (x + 7 + x + x + 3) = (3x + 10) According to the question, 
Since the number of balls cannot be negative, Therefore, x = 6
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