Ben placed a stone in an empty rectangular tank, 50cm long and 40cm wide. He then filled the tank with water flowing from a tap at a rate of 10 liters per minute. it took 3 min to fill the tank to a depth of 18cm to cover the stone completely. Find the volume of the stone. please Help!

1 answer

amount of water poured in = 3(10) = 30 litres
= 30,000 cm^3

height of water without the stone --- h cm

h(40)(50) = 30000
h = 15 cm

when the stone is included, h = 18 cm
so the difference of 3 cm must have been caused by the stone

Volume for the extra 3 cm height
= 3(40)(50) = 6000 cm^3

volume of stone = 6000cm^3