Question
PSLE
A box contained pink balls and gold balls. 70% of the balls were gold. After some black balls were added to the box, 35% of the balls were gold. What percentage of the balls in the box were black?
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PSLE
A box contained pink balls and gold balls. 70% of the balls were gold. After some black balls were added to the box, 35% of the balls were gold. What percentage of the balls in the box were black?