Concrete can be purchased by the cubic yard. How much will it cost to pour a slab 18 feet by 18 feet by 4 inches for a patio if the concrete costs $41.00 per cubic yard?
There are 3 feet in one yard. Thus we have 6*6 yards * 1/9 yard.
That's 36/9 = 4 cubic yards.
41*4 = 164 dollars.
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