| 123.4÷4÷25 | 48×25 | 5.8×101 |
| 1.2×25×4 | 46×6.8+6.8×54 | 99×7.9+7.9 |
| 101×0.38-0.38. |
| 解:①123.4÷4÷25, =123.4÷(4×25), =123.4÷100, =1.234; |
=12×4×25,
=12×(4×25),
=12×100,
=1200;
③5.8×101,
=5.8×(100+1),
=5.8×100+5.8,
=580+5.8,
=585.8;
④1.2×25×4,
=1.2×(25×4),
=1.2×100,
=120;
⑤46×6.8+6.8×54,
=6.8×(46+54),
=6.8×100,
=680;
⑥99×7.9+7.9,
=7.9×(99+1),
=7.9×100,
=790;
⑦101×0.38-0.38,
=0.38×(101-1),
=0.38×100,
=380;
分析:①运用一个数除以2个数,可以用这个数除以这两个数的积进行计算.
②④运用乘法的结合律及交换律进行解答即可.
③⑤⑥⑦运用乘法的分配律进行解答即可.
点评:完成本题要注意分析式中数据,运用合适的简便方法计算.