五年級(jí)奧數(shù)題:湊整化簡(jiǎn)

字號(hào):

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