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五年級(jí)奧數(shù)題:湊整化簡(jiǎn)

時(shí)間:2015-12-17 14:15:00   來(lái)源:無(wú)憂考網(wǎng)     [字體: ]
計(jì)算 :51.2 ×8.1 + 11 ×9.25 + 537 ×0.19

答案與解析:

稍作處理,題中數(shù)字就能湊整化簡(jiǎn),

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