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计算下面各题,能用简便方法的要用简便方法计算0.25×185×405.09×10.7-0.7×5.0910.1×2.3618.09-7.5×(0.14+1.06)15.6-1.25-3.756.81+6.81×99.

题目详情
计算下面各题,能用简便方法的要用简便方法计算 
0.25×185×40        
5.09×10.7-0.7×5.09          
10.1×2.36
18.09-7.5×(0.14+1.06)
15.6-1.25-3.75           
6.81+6.81×99.
▼优质解答
答案和解析
(1)0.25×185×40
=0.25×40×185
=10×185
=1850;
(2)5.09×10.7-0.7×5.09
=5.09×(10.7-0.7)
=5.09×10
=50.9;
(3)10.1×2.36
=(10+0.1)×2.36
=10×2.36+0.1×2.36
=23.6+0.236
=23.836;
(4)18.09-7.5×(0.14+1.06)
=18.09-7.5×1.2
=18.09-9
=9.09;
(5)15.6-1.25-3.75
=15.6-(1.25+3.75)
=15.6-5
=10.6;
(6)6.81+6.81×99
=6.81×(1+99)
=6.81×100
=681.