Level 3
The figure, not drawn to scale, shows an empty tank measuring 20 cm by 15 cm by 15 cm. Water flows from Tap A at a rate of 300 mℓ per minute and from Tap B at a rate of 180 mℓ per minute. Tower X and Tower Y have a base area of 20 cm2 and 30 cm2 respectively. Water is drained out of the container at a rate of 130 mℓ per minute. Find the height of the water level after 13 minutes.
5 m
Level 3
A rectangular tank measuring 120 cm by 50 cm by 100 cm is 50% filled with water. 10 identical pails of water that are completely filled are then scooped out from it. The water level drops to 45 cm. The remaining amount of water in the tank is later poured into a container that contains 40 litres of water. The water is then drained out through a tap found at the bottom of the container at 10 litres per minute.
  1. What is the capacity of each pail?
  2. How long did it take to drain the water from the container completely? Answer in terms of minutes.
5 m
Level 3
The figure shows 2 tanks, Tank X and Tank Y. Tank X is completely empty while Tank Y is filled with water to the brim. Water from Tap A flows in at a rate of 1.2 litres per minute while water drains from Tap B at a rate of 0.72 litres per minute. Both taps are turned on at the same time. After some time, the heights of the water level in both tanks became the same.
  1. Find the time taken for the heights of the water level to be the same in both tanks.
  2. Find the height of the water level at that point of time.
5 m