Nor sure how pee gravel is packed, but you need enough for 64 cubic feet.
It depends how deep you want the gravel to cover, if you want it to be 2 inches deep it's going to cost more than 5 inches. Also it depends how big the gravel is cut, I think that the smaller the gravel is the more it costs.
about 71 cubic metres of gravel i think
You will need 65.93 cubic yards or 84.6 tons of gravel.
It depends how deep you go. If you do 2 inches deep the area will require at least 0.7 cubic yards (about 1,710 pounds) of gravel.
16 sq ft*0.5 ft = 8 cubic feet.
You'll need about 28.704 cubic yards (37 tons) of gravel.
Plan on about 2.2 cubic yards (2.8 tons) of gravel.
You will need about 463 cubic yards (around 594 tons) of gravel for this area.
16.36 cubic yards.
You would need about 13 cu yards or about 15 tons.
You will need 20 cubic yards or 25.7 tons of gravel.
about 18 cubic feet.