How many bricks, each measuring 25 cm x 11.25 cm x 6 cm, will be needed to build a wall 8 m long, 6 m high and 22.5 cm thick?
We know that,
Volume of cuboid = Length × Breadth × Height
Therefore,
Volume of each brick = 25 × 11.25 × 6
= 1687.5 cm3
Volume of wall = 800 × 600 × 22.5
= 10800000 cm3
Therefore,
Number of bricks = 
= 6400
Hence, option C is correct
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