题目内容
| 下面各题怎样简便就怎样计算 (48+463)+337 |
149+(151+236) |
| 644+758-244 | 986-301 |
| 236+197. |
分析:(1)(2)根据加法结合律简算;
(3)根据加法交换律简算;
(4)(5)根据凑整法简算.
(3)根据加法交换律简算;
(4)(5)根据凑整法简算.
解答:解:(1)(48+463)+337
=48+(463+337)
=48+800
=848;
(2)149+(151+236)
=149+151+236
=300+236
=536;
(3)644+758-244
=644-244+758
=200+758
=958;
(4)986-301
=986-300-1
=686-1
=685;
(5)236+197
=236+200-3
=436-3
=433.
=48+(463+337)
=48+800
=848;
(2)149+(151+236)
=149+151+236
=300+236
=536;
(3)644+758-244
=644-244+758
=200+758
=958;
(4)986-301
=986-300-1
=686-1
=685;
(5)236+197
=236+200-3
=436-3
=433.
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.
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