### Quandaries Queries at Math Central

Nov 17, 2006 · How much concrete will i need for a hole that is 20 feet deep 20 inches in diameter with a 8inch pipe in it. I need to know how much concrete on the outside of the 8inch pipe. Answered by Penny Nom. 5 yards of concrete: : From jon: To mix 5 yards of concrete, how many loads will I need to mix in a cubic feet mixer? Thanks, jon