Question

简便计算下面题目？

41.2*5.5+53.7*4.5+5*1.25

Answer 1

先乘积再相加一共是474.5

Answer 2

41.2*5.5+53.7*4.5+5*1.25

=5*（41.2*1.1+53.7*0.9+1*1.25）

=5*[41.2*(1+0.1)+53.7*(1-0.1)+1.25]

=5*(41.2*1+41.2*0.1+53.7*1-53.7*0.1+1.25)

=5*(41.2+4.12+53.7-5.37+1.25)

=5*94.9

=474.5

Answer 3

41.2×5.5+53.7×4.5+5×1.25
解 41.2×5+41.2×0.5+53.7×4+53.7×0.5+12.5×0.5
=（41.2+53.7+12.5）×0.5+41.2×5+53.7×4
=53.7+41.2×5+53.7×4
=（41.2+53.7）×5
=（100-5.1）×5=474.5

Answer 4

41.2*5.5+53.7*4.5+5*1.25
【提取公因数5】
=5x(41.2*1.1+53.7*0.9+1.25)
=5x（45.32+48.33+1.25）
=5x(93.65+1.25)
=5x94.9
=474.5

Answer 5

41.2×5.5+53.7×4.5+5×1.25
=41.2×5.5+（41.2+12.5）×4.5+5×1.25
=41.2×5.5+41.2×4.5+12.5×4.5+5×1.25
=41.2×（5.5+4.5）+1.25×45+5×1.25
=41.2×10+1.25×（45+5）
=412+1.25×50
=412+62.5
=474.5
在计算简便运算时，首先考虑数字之间的关系，能直接凑整的，运用运算律直接运算；不能直接凑整的，拆分最易凑整的数字，然后再计算，