A mark at 5/8 of an inch on a ruler is located after 1/2 inch and before 1 inch. The fifth mark on the ruler from the left is 5/8 inch if the ruler divides inches into eighths. The 10th mark is where the ruler splits an inch into sixteenths.
To identify whether the ruler marks in eighths or sixteenths, count the number of markings between one inch mark and the next. Typically, a number and a longer line are used to indicate inches.
The lines used to indicate half-inches, quarter-inches, eighth-inches, and sixteenth-inches get shorter and shorter. The distance between the ruler’s left end and the 1-inch mark is 0.5 inches. The next line is 5/8 inch on a ruler that divides inches into eighths. It is two lines away from the half-inch point on a ruler that divides inches into 16ths.