早教吧 育儿知识 作业答案 考试题库 百科 知识分享

合理灵活计算.7.8×0.98135.8+27.5+(62.5-35.8)12×0.25+8.8×2.59÷2.4-4.2÷2.4.

题目详情
合理灵活计算.
7.8×0.98                           
135.8+27.5+(62.5-35.8)
12×0.25+8.8×2.5                   
9÷2.4-4.2÷2.4.
▼优质解答
答案和解析
(1)7.8×0.98
=7.8×(1-0.02)
=7.8-7.8×0.02
=7.8-0.156
=7.644

(2)135.8+27.5+(62.5-35.8)
=135.8+27.5+62.5-35.8
=(135.8-35.8)+(27.5+62.5)
=100+90
=190

(3)12×0.25+8.8×2.5
=12×0.25+88×0.25
=(12+88)×0.25
=100×0.25
=25

(4)9÷2.4-4.2÷2.4
=(9-4.2)÷2.4
=4.8÷2.4
=2