rá (3) noun "arm" (LT2:335, there spelt râ; probably obsoleted by # 2 (and # 1) above. In Tolkien's later Quenya, "arm" is ranco)
Quenya
ranga
yard, full pace
ranga
noun. yard, full pace
rá
arm
lár
league
lár (1) noun "league", a linear measure, 5000 rangar (q.v.). A ranga was approximately 38 inches, so a lár was "5277 yards, two feet and four inches [ca. 4826 m], supposing the equivalence to be exact" - close enough to our league of 5280 yards to justify this translation. The basic meaning of lár is "pause"; in marches a brief halt was made for each league. (UT:285)
ranco
arm
ranco ("k")noun "arm", stem *rancu- given the primitive form ¤ranku, hence also pl. ranqui ("q")(RAK)
ranga (pl. rangar is attested) noun "yard, full pace". This Númenórean linar measure was "slightly longer than our yard, approximately 38 inches [= 96.5 cm]". (UT:285, 461)