Question
PSLE
A box contained grey balls and green balls. 60% of the balls were green. After some black balls were added to the box, 36% of the balls were green. What percentage of the balls in the box were black?
2 m

Click button first when a symbol is required. X

PSLE
A box contained grey balls and green balls. 60% of the balls were green. After some black balls were added to the box, 36% of the balls were green. What percentage of the balls in the box were black?