Division From a Printer’s Viewpoint
Overview: Commercial printers deal with division constantly in figuring the number of finished-size sheets that can be cut from the large “parent” size sheets they normally receive from the paper supplier. It’s a real-world exercise not many people are aware of.
* The procedure is to divide one dimension of the parent sheet by one dimension of the finished sheet, then repeat the process for the remaining dimensions. Then do it all over again, reversing the two finished sheet dimensions, to get the most economical cut of the paper. So if X and Y are the parent sheet dimensions, and A and B are the finished sheet dimensions, divide X by A, and Y by B, then multiply the answers together to get the total number of sheets. Then repeat the process, but divide X by B, and Y by A.
* A variation is to use paper on a roll, figuring both ways to have the least amount of waste left over after cutting.
* Visualize the process by drawing the large sheet, indicating where the cuts for the smaller sheets would be. Draw proportionally, letting one inch equal one centimeter, to accurately visualize where the waste is, and whether an extra sheet could be cut from it.
* Parent sheets are around 23″ by 35″.
* Combine with an art project, by calculating the number of feet of roll-type bulletin board paper needed for each student to have two pieces of 8″ by 10″ colored paper. Measure and draw with markers to indicate where the cut lines would be, figured both ways.