Question
PSLE
A box contained red balls and black balls. 40% of the balls were black. After some purple balls were added to the box, 36% of the balls were black. What percentage of the balls in the box were purple?
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PSLE
A box contained red balls and black balls. 40% of the balls were black. After some purple balls were added to the box, 36% of the balls were black. What percentage of the balls in the box were purple?