Convert from palm [US, Roman major] to step

Unit Definition (palm [US, Roman major])
A palm, when used as a unit of length, is usually four digits or three inches, i.e. 7.62 cm (for the international inch). The width of an adult human male palm is indeed about 10 centimetres.In English this unit has mostly fallen out of use, as do others based on the human arm: digit (¼ palm), finger (7/24 palm), hand (4/3 palms), shaftment (2 palms), span (3 palms), cubit (6 palms) and ell (15 palms).

Unit Definition (step)
The step is a traditional unit of distance, equal to 1/2 pace. The step is traditionally equal to 30 inches or 76.2 centimeters. However, U.S. marching bands often use a shorter step of 22.5 inches (57.15 centimeters), so that 8 steps are made every 5 yards; this works well on American football fields, which have a chalkline every 5 yards. Using this shorter step is called marching "8 by 5."