20道计算题四年级乘法带答案 1. 67 ×21 ＋18 ×21 + 85 ×79 2. 375 ×480 + 6250 ×48 3. 321 ×81 + 321 ×19 4. 222222 ×999999 5. 333333 ×333333 6. 654321 ×909090 +654321 ×90909 7. 34 ×3535 －35 ×3434 8. 345345 ÷15015 9. 75 ×45 + 17 ×25 10. (48 ×75 ×81）÷（24 ×25 ×27） 【答案详解】 1. 67 ×21 ＋18 ×21 + 85 ×79 =21×(67+18)+85×79 =21×85+85×79 =85×(21+79) =8500 2. 375 ×480 + 6250 ×48 =480×(375＋625) =480000 3. 321 ×81 + 321 ×19 =321×(81+19) =32100 4. 222222 ×999999 =222222×(1000000－1) =222222000000－222222 =222221777778 5. 333333 ×333333 =111111×999999 =111111×(1000000－1) =111111000000－111111 =111110888889 6. 654321 ×909090 +654321×90909 =654321×999999 =654321×(100000－1) =654321000000－654321 =654320345679 7. 34 ×3535 －35 ×3434 =34×35×101－35×34×101 =0 8. 345345 ÷15015 =345×1001÷(15×1001) =345÷15×1001÷1001 =23 9. 75 ×45 + 17 ×25 =25×3×45+17×25 =25×(135+17) =25×152 =25×4×38 =3800 10. (48 ×75 ×81）÷（24 ×25 ×27）×3 =18 ÷24×75÷25×81÷27 =2×3 =48 本文来源：https://www.wddqw.com/doc/49fe56f4bbf67c1cfad6195f312b3169a451ea63.html