Question

能简便的用简便方法计算． 75+8.95+10.25 6.38-1.8+3.62 95÷1.25÷0.8 &...

能简便的用简便方法计算． 75+8.95+10.25 6.38-1.8+3.62 95÷1.25÷0.8 9.4×5-10.6． 7×9.9+0.1×0.7 13.8+15.6÷0.4． 85×1.25+0.85×1.75 2.15×0.9+21.5×0.11．

Answer 1

（1）75+8.95+10.25    
=75+（8.95+10.25）
=75+19.2
=94.2

（2）6.38-1.8+3.62
=（6.38+3.62）-1.8
=10-1.8
=8.2

（3）95÷1.25÷0.8
=95÷（1.25×0.8）
=95÷1
=95

（4）9.4×5-10.6
=47-10.6
=36.4

（5）7×9.9+0.1×0.7
=7×9.9+0.01×7
=7×（9.9+0.01）
=7×9.91
=7×（10-0.09）
=7×10-7×0.09
=70-0.63
=69.37

（6）13.8+15.6÷0.4
=13.8+39
=52.8

（7）85×1.25+0.85×1.75   
=106.25+1.4875
=107.7375

（8）2.15×0.9+21.5×0.11
=2.15×0.9+2.15×1.1
=2.15×（0.9+1.1）
=2.15×2
=4.3