(8700+870+87) ÷87 =8700÷87+870÷87+87÷87 =100+10+1 =111 追问: 么么 哒,谢谢了 追问: 64.2×87+0.642×1300 那这到哪 回答: 64.2×87+0.642×1300 =0.642x100x87+0.642x1300 =0.642x(8700+1300) =0.642x10000 =6420 追问: 那100怎么来的 回答: 0.642x100=64.2