concrete installation costs

how much does concrete cost per square foot?
i’m doing a project for math that requires me to build a park. i have to find prices of things to put in a park and i need to find the price of concrete to be installed and all that stuff. i have to find it by square foot with installation and service.
Concrete is almost always sold by the cubic yard so, you have to know how “deep” your sidewalks and other structures are going to be. Normall sidewalks are 3″ to 4″ deep (which is 1/3 or 1/4 of a foot. A cubic yard is 3 feet by 3 feet by 3 feet so, if your sidewalks are going to be 1/4 of a foot, you can get 108 square feet of space.
Concrete sell for between US$70. and US$100 per cubic yard depending on where you live. but it could be higher (up to $150) if it is in short supply.
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Driveway Installation