有一批食品罐頭，標(biāo)準(zhǔn)質(zhì)量為每聽(tīng)454 g，現(xiàn)抽取10聽(tīng)樣品進(jìn)行檢測(cè)，結(jié)果如下表(單位：g)：

這10聽(tīng)罐頭的總質(zhì)量是多少？

答案：
解析：

　　解：把超過(guò)標(biāo)準(zhǔn)質(zhì)量的克數(shù)用正數(shù)表示．不足標(biāo)準(zhǔn)質(zhì)量的克數(shù)用負(fù)數(shù)表示，列出10聽(tīng)罐頭的質(zhì)量與標(biāo)準(zhǔn)質(zhì)量的差值表如下：(單位：g)：

　　這10聽(tīng)罐頭的質(zhì)量與標(biāo)準(zhǔn)質(zhì)量的差值和為：

　　(－10)＋5＋0＋5＋0＋0＋(－5)＋0＋5＋10＝[(－10)＋10]＋[(－5)＋5]＋(5＋5)＝10(g)．

　　因此，這10聽(tīng)罐頭的總質(zhì)量為454×10＋10＝4 550(g)．


提示：

　　當(dāng)已知的一列數(shù)中和數(shù)都比較大，但都與某一個(gè)數(shù)比較接近時(shí)，一般就以這“某一個(gè)數(shù)”為基數(shù)，超過(guò)的記為正，不足的記為負(fù)，這樣計(jì)算起來(lái)比較快捷、簡(jiǎn)便．


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