早教吧 育儿知识 作业答案 考试题库 百科 知识分享

(-3.85)x(-13)+(-13)x(-6.15)+0.79x7/15+8/15x0.79简便运算999+24/25x(-5)

题目详情
(-3.85)x(-13)+(-13)x(-6.15)+0.79x7/15+8/15x0.79简便运算
999+24/25x(-5)
▼优质解答
答案和解析
(-3.85)x(-13)+(-13)x(-6.15)+0.79x7/15+8/15x0.79
=(-13)(-3.85-6.15)+0.79x(7/15+8/15)
=130+0.79
=130.79
999+24/25x(-5)
=999+(1-1/25)×(-5)
=999-5+1/25×5
=999-5+1/5
=994又1/5