You are mixing cement on the job site. There are 7 mixers that are 18 cubic ft. each. The time it takes to load, mix and empty the mixer is 9 minutes. How many cubic feet of cement can be produced per hour?

You are mixing cement on the job site. There are 7 mixers that are 18 cubic ft. each. The time it takes to load, mix and empty the mixer is 9 minutes. How many cubic feet of cement can be produced per hour?