数学:要3道简便运算的小数脱式计算(四年级的)!急上加急!~

25×1/4加25×0.25
1.999减1加0.001
99×0.36529587
OK

这样的题目很多，举例如下：
4.1×67.2+4.8
9.42×2.1+4.6
8.24×5.4+6.4
1.2×0.4+7.8
3.08×7.5+4.3
4.17-3.5×2.6
4.1×85.1+7.4
1.25×9.01+0.3
84.4+1.4×5.2
4.27×0.35+4.8
9-3.6×1.25 8×0.4-2.1
5.2×4.3+8.7
9.4×7.2-7.4
6.04×1.04+8.4
4.81×2.4+1.02
8.04×9.4-0.46
7.05-2.4×5.4
7.42-3.15×0.23
24.5×0.21-2
4.78+0.28×5.1
27.1×0.3+5.8
9.04×0.4+3.6
4.1×0.6+9.4
2.7+7.3×2.01
3.48×0.24+8.6
8.14-2.3×0.42
7.5×2.4-3.4
7.1×9.4-4.07
5.12-8.14×2.1
4.12×1.08-0.25
0.45×2.8-0.04

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