How many bags of play sand would I need to cover a area 10 ft. round by 2 in. deep of each bag of sand is .5 cubic ft.
You need 13.09 cubic feet of sand (22/7)*(5^2)*(1/6), so 26 bags (1/2 cubic yard) should do it.
It depends on how much sand the sand bags contain.
You will need 1/2 cubic YARD of sand.