题目内容
99
×49.
| 97 | 98 |
分析:根据数字特点,把99
拆成(99+
),然后运用乘法分配律写成99×49+
×49,再把99看作(100-1),计算得出结果.
| 97 |
| 98 |
| 97 |
| 98 |
| 97 |
| 98 |
解答:解:99
×49,
=(99+
)×49,
=99×49+
×49,
=(100-1)×49+
,
=4900-49+48
,
=4900-49+48+
,
=4900-1+
,
=4899
.
| 97 |
| 98 |
=(99+
| 97 |
| 98 |
=99×49+
| 97 |
| 98 |
=(100-1)×49+
| 97 |
| 2 |
=4900-49+48
| 1 |
| 2 |
=4900-49+48+
| 1 |
| 2 |
=4900-1+
| 1 |
| 2 |
=4899
| 1 |
| 2 |
点评:此题考查了学生根据数字特点进行灵活简算的能力.
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