小红参加六年级趣味数学竞赛,共有20道题,每做对一道得5分错一题,错一题得-3分,不
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=16\u00f78
=2\uff08\u9053\uff09\u9519
20-2=18\uff08\u9053\uff09\u5bf9
\u9e21\u5154\u540c\u7b3c\u7684\u9898\u76ee
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5x-2*\uff0820-x\uff09=79\uff0c\u89e3\u5f97x=17\uff0c\u5373\u5c0f\u7ea2\u505a\u5bf9\u4e8617\u9898\u3002
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"小红参加六年级趣味数学竞赛,共有20道题,每做对一道得5分错一题,错一题得-3分,不"啥意思？？？？？
绛旓細锛20脳5-84锛壝凤紙5--3锛夊氨鏄姞璐熶笁 =16梅8 =2锛堥亾锛夐敊 20-2=18锛堥亾锛夊 楦″厰鍚岀鐨勯鐩
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