题目内容
简便算法. 7.28-3.16-2.84 |
6.3+18.2+13.7 | 7.6×10.1 | 8.16×2.4+7.6×8.16. |
分析:(1)运用减法的性质简算;
(2)运用加法交换律简算;
(3)把10.1看作10+0.1,运用乘法分配律的逆运算简算;
(4)运用乘法分配律的逆运算简算.
(2)运用加法交换律简算;
(3)把10.1看作10+0.1,运用乘法分配律的逆运算简算;
(4)运用乘法分配律的逆运算简算.
解答:解:(1)7.28-3.16-2.84,
=7.28-(3.16+2.84),
=7.28-6,
=1.28;
(2)6.3+18.2+13.7,
=6.3+13.7+18.2,
=20+18.2,
=38.2;
(3)7.6×10.1,
=7.6×(10+0.1),
=7.6×10+7.6×0.1,
=76+0.76,
=76.76;
(4)8.16×2.4+7.6×8.16,
=(2.4+7.6)×8.16,
=10×8.16,
=81.6.
=7.28-(3.16+2.84),
=7.28-6,
=1.28;
(2)6.3+18.2+13.7,
=6.3+13.7+18.2,
=20+18.2,
=38.2;
(3)7.6×10.1,
=7.6×(10+0.1),
=7.6×10+7.6×0.1,
=76+0.76,
=76.76;
(4)8.16×2.4+7.6×8.16,
=(2.4+7.6)×8.16,
=10×8.16,
=81.6.
点评:完成本题要注意分析式中数据,运用所学的运算定律或运算性质进行计算.
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