Rithvik's Blog 11+

Sarah has a collection of 120 marbles. She decides to give 25% of her marbles to her friend and then loses 1/3 of the remaining marbles. How many marbles does Sarah have left?

There are 2200 litres of water available in a tank. After 550 litres of water have been used, what is the percentage of water that remains? What is the percentage of water used?