



 
Hi Carla, I am going to imagine that you cover the entire site with 6 inches of rock. There are 3 feet in a yard and 36 inches in a yard so the volume of rock needed to cover the site would be \[\frac{50}{3} \times \frac{60}{3} \times \frac{6}{36} \mbox{ cubic yards.}\] Now you want to remove the rock you don't need. That's a solid region, 20 feet by 16 feet and 6 inches deep. What is the volume of rock you don't need? What is the volume of rock you do need? Penny  


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