Question
PSLE
A box contained brown marbles and blue marbles. 40% of the marbles were blue. After some gold marbles were added to the box, 20% of the marbles were blue. What percentage of the marbles in the box were gold?
2 m

Click button first when a symbol is required. X

PSLE
A box contained brown marbles and blue marbles. 40% of the marbles were blue. After some gold marbles were added to the box, 20% of the marbles were blue. What percentage of the marbles in the box were gold?