Level 3 A rectangular tank is filled with water to a height of 4 cm. Its rectangular base measures 25 cm by 8 cm. When 12 litres of water are poured into the tank, the water level rises to 25 of the height of the tank. Find the height of the tank.
Level 3
Ron and Benny take 4 days to assemble a toy plane. Benny and Jerry take 6 days to build the same toy plane while Ron and Jerry take only 3 days. How many complete days would the three of them take to build the same toy plane?