Question

0.87×3.16+4.64用简便算法计算？

Answer 1

解:运用乘法分配律将0.87化为(0.8+0.07)与3.17分别相乘，然后按四则运算法则进行计算。计算过程
0.87ⅹ3.16+4.64
=(0.8+0.07)x3.16+4.64
=2.528+0.2212+4.64
=7.3892(四舍五入保留两位小数)
≈7.39。

Answer 2

0.87×3.16+4.64用简便算法计算？
0.87×3.16+4.64
=3x0.29x4x0.79+4x4x0.29
=4x0.29x[3x(0.8-0.01)+4]
=4x0.29x[2.4-0.03+4]
=4x(0.3-0.01)x6.37
=(1.2-0.04)x6.37
=1.16x6.37
=1.16x6+1.16x0.4-1.16x0.03
=6.96+0.464-0.0348
=6.96+0.4292
=7.3892