A slab measure (40 cm x 20 cm x 25/2 cm). How many slabs will be required for a wall 35 m long, 2 m high and .5 m thick?

Question

Find the number of tiles, 20 cm x 14 cm x 6 cm, required to construct a wall 20 m long, 10 m high and 70 cm thick.
If 10% of the wall is filled with mortar.