4.(1)75x3+75 =225+75 =300个 (2)75x3-16 =225-16 =209个 5. 290-15x18 =290-270 =20吨 6. 60x5+350 =300+350 =650套苏教版三年级下册数学补充习题第31页答案 http://m.ksjqmj.com/sannianjidaan/3383.html 推荐访问