lǎo / shī / yòng / jù / tǐ / shù / jù / shuō / míng / tiáo / hé / píng / jūn / shù / de / jì / suàn / fāng / fǎ老师用具体数据说明调和平均数的计算方法。The teacher used specific data to explain how to calculate the harmonic mean.