第1个回答 推荐于2016-01-28
解:1。(15/27)x11+(11/27)x12
=(16/27--1/27)x11+(11/27)x(11+1)
=(16/27)x11--(1/27)x11+(11/27)x11+(11/27)x1
=[(16/27)+11/27)]x11--(11/27)+(11/27)
=11.
2。(21/35)x19+(19/35)x14
=(21/35)x19+(19/35)x14
=(21x19)/35+(19x14)/35
=[19(21+14)]/35
=19.本回答被提问者和网友采纳