How many bags of sand will I need for my lawn?

Question

I need to have 4cm in depth for an 85 square meter lawn. How many 25kg bags of sand will it take?

Answer 1

4cm (0.04 metres) X 85 = 3.4 cubic metres
1.6 tonnes of sand = 1 cubic metre
Therefore 3.4 cubic metres = 3.4 X 1.6 tonnes = 5.4 tonnes
! tonnes = 1000 kgs = 4 X 250 kg bags
Therefore 5.4 tonnes = 5.4 X 4 250 kg bags = 21.6 bags