Convert from span to pie [Spanish]

Unit Definition (span)
Span is the width of a human hand, from the tip of the thumb to the tip of the pinky finger.

Unit Definition (pie [Spanish])
The pie is a traditional foot of Spain. The pie equals 1/3 vara or 12 pulgadas. The pie used in Spain is about 27.86 centimeters or 10.97 inches, but in Spanish Latin America the pie is generally longer.