Tosefta על בבא בתרא 213:1

Three people that came down to evaluate [the property of orphans in order to ascertain the financial support for the dead man's wife and children; see Rashbam on Bava Batra 107a:7:1]—one says "It's worth 100 zuz" and two say "200"; [or] one says "200" and two say "100", the lone voice is annulled in its minority [so in both cases the majority stands]. One says "It's worth 100 zuz", one says "80 zuz (= 20 selaim)", one says "120 zuz (= 30 selaim)"—it is evaluated at 100 zuz (the average of all 3). Rabbi Lazar bar Rabbi Tzadok says: They evaluate it at 90 zuz (= dinar) [we ignore the highest value and average the two lowest value, 80 and 100]. Others say: They do an evaluation between them (take the range, = 40 zuzim) and evaluate them as a third [so they take the lowest value, 80 zuz, and add the third of the range = 93 1/3 zuz].