Data Sufficiency (DS) | Re: If a bag contains only red and blue balls and probability of picking

Nice question. Since there are only reds and blues then that means that probabilities are split 50:50, and thus they should be of equal quantities. D1: provides an exact quantity which +/- and resulting change to probability which should give us the final number D2: Only one number can be 30 less than the total, equaling to the rest of the amount of balls.

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