A cistern, internally measuring 150cm x 120cm x 110cm, has 129600cm³ of water in it. Porous bricks are placed in the water until the cistern is full to the brim. Each brick absorbs one-seventeenth of its own volume of water. How many bricks can be put in without overflowing the water, each brick being 22.5cm x 7.5cm x 6.5cm

Volume of cistern = 150 × 120 × 110 = 1980000cm³
Volume to be filled in cistern = 1980000 - 129600 = 1850400cm³
Let x numbers of porous bricks were placed in the cistern.
Volume of x bricks = x × 22.5 × 7.5 × 6.5 = 1096.875x
As each brick absorbs one-seventeenth of its volume, therefore, volume absorbed by these bricks = x/17(1096.875)
→ 1850400 + x/17(1096.875) = (1096.875)x
→ 1850400 = 16x/17(1096.875)
x = 1792.41
Therefore, 1792 bricks were placed in the cistern.