Question 138277
18 times 4 times .5 gives you the number of cubic yards required.  And $3.50 times the answer to the first part gives you the answer to the second part.  And, please, please, please ask your instructor where I can get concrete for $3.50 a cubic yard!  Ready-mix in a truck averages about $65.00 per yard plus short-load, fuel, environmental fees, and other costs.  That's not to mention that a driveway 18 inches thick is ridiculous.  Driveways are 4 to 6 INCHES thick.