Q)
A bag contains white, black and red balls only. A ball is drawn at random from the bag if the probability of getting a white balls is $\large\frac{3}{10} $ and that of black is $\large\frac{2}{5}$, then find the probability of getting a red balls. If the bag contains 20 black balls, then find the total number of balls in the bag.
1 Answer
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