The way they have it is just too ambiguous, especially for people who struggle with the metric system.įor the life of me, I cannot figure out why this picture has more than a couple of views. I'd rather they put cm after the number 1, and shrink the mm and nestle it down next to the mm markings, between zero and 5mm. So why do they mark the metric side "mm" when they number the centimeters?!! Usually these same rulers mark the other side as "inches" and the inches are numbered. Change the diagonal value in the input field until the edge of the. For your convenience, the corresponding sign is plotted under the scale of the ruler. Its standard width is 3.37 inches (3 38 inches), or 85.6 mm (8 centimeters, 56 millimeters) for the metric measurement. So now I look at such loose labeling as a symbol of the incompetence of ruler manufacturers. You can also calibrate the on-screen ruler using a bank payment card. Many tended to get confused, thinking the mm indicates that the numbers are millimeters. I originally took the picture as part of a worksheet to help my students distinguish between imperial and metric measurement. Why manufacturers seem to be STUPID, INCOMPETENT, or both.īut I should add that they at least used the correct mm (millimeter) abbreviation rather than MM as I have seen on other rulers! AND they positioned the "mm" relatively well. Ruler … Why mark mm (millimeters - which aren't numbered) and not the cm (centimeters - which are numbered)? Labeling the 1 as "1 cm" would help a student understand that the numbers refer to the largest markings while the mm refers to the smallest markings.