3.6 cubic yards will be enough.
You will need 17.8 cubic yards of concrete.
10.67 Cubic Yards
532.4074 yards of concrete, round up to 533 yards.
6.94 Cubic Yards
10 yards
6.67 Cubic Yards
4.074 cubic yards for every foot the slab is thick.
15 cubic yards
15 cubic yards
39.1116 cubic yards
At 4" thick you will need 1.23 cubic yards.
That depends on the length and width of your construction.