A person learns something new with every project, and this one was no different. 

First, I measured and laid out the side walk, then calculated the amount of concrete I needed. I goofed big time, and did not realize it until "place" day (You POUR Bourbon, you PLACE concrete). The 80 pounds sacks of Sackrete (cement and aggregate all ready mixed) are about 6/10ths of a CUBIC FOOT each, and I calculated it as 6/10 of a cubic yard, each. I had just 1/27th of the concrete I needed. Hint: always have somebody else double check you figures, and don't get in a big hurry like I did. Anyway, it took 85 of the 80 pound bags and 14 hours of labor for each person there. NEVER AGAIN. I save my concrete projects up until I have enough to justify a BIG truck delivering it to me, pre-mixed. (Note, I am 3/4 mile from a ready mix plant, and if I am willing to be patient, wait until they have a truck returning with a yard or two, and be ready to pour (whoops, I mean "place") on a moments notice, they will give me exceptionally good prices.