I try by strict Math, the anwser should be between 78 and 81

來源: 於 2012-01-03 12:09:54 [舊帖] [給我悄悄話] 本文已被閱讀：次

the back times are longer.Cs we have to use small number in the dinominatod the error is big. If the anwser is 81,we also can't use your formula....