Level 3
A container holds some water up to a height of 71 cm. When 6 identical plastic balls are put into the container, the water level rises by 18 cm. One plastic ball is then removed from the tank, replaced by one metallic ball. The water level increases to 136 cm.
Find the ratio of the volume of 1 plastic ball to 1 metallic ball.
If the base area of the container is 150 cm2, find the difference in the volume between the metallic ball and the plastic ball. Give the answer in cm3.
Level 3
A rectangular container 100 cm by 50 cm by 45 cm was 20% filled with water. A tap was turned on to fill it up with water at a rate of 9 ℓ /min. Every 30 seconds after the tap was turned on, an iron ball of volume 500 cm3 was added to the container. How many iron balls of the same volume would there be in the container when the container is 100% filled with water?
Level 3
It takes Faucet X 15 minutes to fill a tank measuring 14 cm by 8 cm by 12 cm completely while it takes Faucet Y only 10 minutes. How long will it take to completely fill the tank with water if both faucets are turned on at the same time and 3 cubic cubes of edges 3 cm, filled with water, are poured into the tank? Leave the answer in minutes and round off to 2 decimal places.
