早教吧 育儿知识 作业答案 考试题库 百科 知识分享

18/17×4/5-4/14×3/517×14×(8/7-14/17)(1/2-1/4/3)×2/5+2/5简便计算

题目详情
▼优质解答
答案和解析
18/17×4/5-4/14×3/5
=18/17×4/5-3/14×4/5
=(18/17-3/14)×4/5
=201/238×4/5
=402/595
17×14×(8/7-14/17)
=17×14×8/7-17×14×14/17
=272-196
=76
(1/2-1/4/3)×2/5+2/5
=(1/2-3/4+1)×2/5
=3/4×2/5
=3/10