Question

数学简便运算，帮我解一下。

简便运算（脱式计算）
41.2×8.1+11×1.25+53.7×1.9

格式：
41.2×8.1+11×1.25+53.7×1.9
=×××××
=×××××
=×××

Answer 1

解：41.2×8.1+11×1.25+53.7×1.9
=41.2×8.1+11×1.25+（41.2×8.1+12.5×1.9）
=（41.2×8.1+41.2×1.9）+（11×1.25+12.5×1.9）
=41.2×（8.1+1.9）+12.5×（1.1+1.9）
=412+37.5
=449.5

Answer 2

41.2×8.1+11×1.25+53.7×1.9
=41.2*(8+0.1)+12.5+1.25+53.7*(2-0.1)
=329.6+4.12+12.5+1.25+107.4-5.37
=449.5+4.12+1.25-5.37
=449.5+0
=449.5

Answer 3

任务

Answer 4

41.2×8.1+11×1.25+53.7×1.9
=41.2×8.1+11×1.25+（41.2×8.1+12.5×1.9）
=（41.2×8.1+41.2×1.9）+（11×1.25+12.5×1.9）
=41.2×（8.1+1.9）+12.5×（1.1+1.9）
=412+37.5
=449.5

Answer 5

41.2×8.1+11×1.25+53.7×1.9
=41.2*(10-1.9)+(10+1)*1.25+53.7*1.9
=412-41.2*1.9+12.5+1.25+53.7*1.9
=412+12.5+1.25+(53.7-41.2)*1.9
=412+12.5+1.25+12.5*(2-0.1)
=412+12.5+1.25+25-1.25
=449.5