五年级奥数题:凑整化简

时间:2015-12-17 14:15:00   来源:无忧考网     [字体: ]
计算 :51.2 ×8.1 + 11 ×9.25 + 537 ×0.19

答案与解析:

稍作处理,题中数字就能凑整化简,

原式=51.2×8.1+11×9.25+(512+25)×0.19

=51.2×8.1+11×9.25+512×0.19+25 ×0.19

=51.2×8.1+51.2 ×1.9+11×9.25+0.25×19

=51.2×10+11×0.25+11×9+0.25×19

=512+0.25×30+99

=611+7.5

=618.5