老师出了两道数学题，有29人做了一道，做对第一题有21人，做对第二题有17人，两题都做对的有几人？ 一班有45人进行测试两道题都做对的有12人第一道题做对的有3...
\u8001\u5e08\u51fa\u4e24\u9053\u9898\uff0c\u670929\u4eba\u81f3\u5c11\u505a\u5bf9\u4e00\u9053\u9898\uff0c\u5176\u4e2d\u505a\u5bf9\u7b2c\u4e00\u9898\u7684\u670921\u4eba\uff0c\u505a\u5bf9\u7b2c\u4e8c\u9898\u7684\u670917\u4eba\uff0c\u4e24\u9898\u90fd\u505a\u5bf9\u768421+17-29=9 \u4eba\uff0c\u4e24\u9053\u9898\u90fd\u5bf9\u7684\u67099\u4eba\u3002
\u505a\u5bf9\u7b2c\u4e00\u9898\u7684\u670921\u4eba\uff0c\u505a\u5bf9\u7b2c\u4e8c\u9898\u7684\u670918\u4eba\uff0c\u5c31\u7b97\u6bcf\u4e2a\u4eba\u90fd\u505a\u5bf9\u4e00\u9053\u9898 21+18=39\uff08\u4eba\uff09\uff08\u6bcf\u4eba\u81f3\u5c11\u505a\u5bf9\u4e00\u9898\uff09
\u4e24\u9898\u90fd\u505a\u5bf9\u7684\u67099\u4eba \u4e00\u4e2a\u4eba\u4f5c\u5bf9\u4e24\u9898 \u4f46\u521a\u624d\u7b97\u4e00\u4e2a\u4eba\u505a\u5bf9\u4e00\u9053\u9898 \u5c31\u4e24\u9898\u90fd\u505a\u5bf9\u7684\u4eba\u4e00\u4e2a\u9876\u4fe9\uff0c\u4f46\u53ea\u80fd\u7b97\u662f\u4e00\u4e2a\u4eba\u800c\u4e0d\u662f\u4e24\u4e2a\uff0c\u521a\u624d21+18=39\uff08\u4eba\uff09\u628a\u4ed6\u4eec\u7b97\u4e86\u4e24\u6b21\uff0c\u53ea\u80fd\u7b97\u4e00\u6b21\uff0c\u6240\u4ee5\u8981\u518d\u51cf\u53bb\u4ed6\u4eec\u4e00\u6b2139-9=30\u4eba
\u6269\u5c55\u8d44\u6599\uff1a
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\u51cf\u6cd5\u4e0e\u52a0\u6cd5\u4e92\u4e3a\u9006\u8fd0\u7b97\uff0c\u9664\u6cd5\u4e0e\u4e58\u6cd5\u4e92\u4e3a\u9006\u8fd0\u7b97\u3002
\u6574\u6570\u7684\u52a0\u51cf\u6cd5\u8fd0\u7b97\u6cd5\u5219\uff1a
1\u3001\u76f8\u540c\u6570\u4f4d\u5bf9\u9f50\uff1b
2\u3001\u4ece\u4e2a\u4f4d\u7b97\u8d77\uff1b
3\u3001\u52a0\u6cd5\u4e2d\u6ee1\u51e0\u5341\u5c31\u5411\u9ad8\u4e00\u4f4d\u8fdb\u51e0\uff1b\u51cf\u6cd5\u4e2d\u4e0d\u591f\u51cf\u65f6\uff0c\u5c31\u4ece\u9ad8\u4e00\u4f4d\u90001\u5f5310\u548c\u672c\u6570\u4f4d\u76f8\u52a0\u540e\u518d\u51cf\u3002
\u52a0\u6cd5\u8fd0\u7b97\u6027\u8d28
\u4ece\u52a0\u6cd5\u4ea4\u6362\u5f8b\u548c\u7ed3\u5408\u5f8b\u53ef\u4ee5\u5f97\u5230\uff1a\u51e0\u4e2a\u52a0\u6570\u76f8\u52a0\uff0c\u53ef\u4ee5\u4efb\u610f\u4ea4\u6362\u52a0\u6570\u7684\u4f4d\u7f6e\uff1b\u6216\u8005\u5148\u628a\u51e0\u4e2a\u52a0\u6570\u76f8\u52a0\u518d\u548c\u5176\u4ed6\u7684\u52a0\u6570\u76f8\u52a0\uff0c\u5b83\u4eec\u7684\u548c\u4e0d\u53d8\u3002\u4f8b\u5982\uff1a34+72+66+28=(34+66)+(72+28)=200\u3002
\u60a8\u597d\uff0c\u4e2d\u516c\u6559\u80b2\u4e3a\u60a8\u670d\u52a1\u3002
\u7ed9\u4f60\u5206\u4eab\u4e00\u4e2a\u516c\u52a1\u5458\u8003\u8bd5(http://gz.offcn.com?wt.mc_id=bd11588)\u590d\u4e60\u5907\u8003\u65b9\u6cd5\u3002\u5e0c\u671b\u5bf9\u4f60\u6709\u7528\u3002
1\u3001\u91cd\u505a\u771f\u9898\uff0c\u628a\u63e1\u89c4\u5f8b
\u5403\u900f\u771f\u9898\u662f\u590d\u4e60\u5907\u8003\u7684\u5fc5\u5907\u4e4b\u9009\uff0c\u771f\u9898\u662f\u4e00\u5207\u8d8b\u52bf\u53d8\u5316\u7684\u6e90\u6cc9\uff0c\u638c\u63e1\u4e86\u771f\u9898\u5c31\u638c\u63e1\u4e86\u516c\u52a1\u5458\u8003\u8bd5\u7684\u547d\u8109\u3002\u56e0\u6b64\uff0c\u5efa\u8bae\u8003\u751f\u5728\u540e\u4e00\u9636\u6bb5\u7684\u590d\u4e60\u4e2d\uff0c\u53ef\u4ee5\u901a\u8fc7\u91cd\u505a\u771f\u9898\uff0c\u53d1\u73b0\u548c\u603b\u7ed3\u81ea\u8eab\u4e0d\u8db3\uff0c\u8fdb\u4e00\u6b65\u628a\u63e1\u7701\u8003\u51fa\u9898\u89c4\u5f8b\u548c\u8003\u8bd5\u91cd\u70b9\uff0c\u4e3a\u6700\u540e\u7684\u51b2\u523a\u590d\u4e60\u505a\u597d\u51c6\u5907\u3002\u8003\u751f\u5728\u91cd\u505a\u771f\u9898\u65f6\u8981\u6ce8\u610f\uff1a
\uff081\uff09\u91cd\u65b0\u8d2d\u4e70\u6216\u6253\u5370\u771f\u9898\uff0c\u4ee5\u514d\u53d7\u5230\u4e0a\u6b21\u505a\u9898\u7684\u5e72\u6270\uff1b
\uff082\uff09\u4f5c\u7b54\u5b8c\u6bd5\u540e\u8981\u8ba4\u771f\u5bf9\u7167\u7b54\u6848\uff0c\u4e0e\u7b2c\u4e00\u6b21\u505a\u771f\u9898\u7684\u60c5\u51b5\u6bd4\u8f83\uff0c\u5c24\u5176\u662f\u5bf9\u4e00\u9519\u518d\u9519\u7684\u9898\u76ee\u8981\u91cd\u70b9\u5206\u6790\uff0c\u53d1\u73b0\u81ea\u5df1\u7684\u4e0d\u8db3\u6240\u5728\uff1b
\uff083\uff09\u5bf9\u6240\u505a\u771f\u9898\u7684\u6750\u6599\u548c\u8bd5\u9898\u7279\u70b9\u8fdb\u884c\u7814\u7a76\uff0c\u660e\u786e\u7701\u8003\u51fa\u9898\u89c4\u5f8b\uff0c\u5c24\u5176\u662f\u5bf9\u5e38\u8003\u9898\u578b\u8fdb\u884c\u603b\u7ed3\uff0c\u8bb0\u8bf5\u4e00\u4e9b\u5e38\u7528\u516c\u5f0f\uff0c\u5b9e\u73b0\u5728\u8003\u573a\u4e0a\u5feb\u901f\u89e3\u9898\u3002
2\u3001\u4e13\u9879\u590d\u4e60\uff0c\u67e5\u6f0f\u8865\u7f3a
\u7ecf\u8fc7\u524d\u671f\u7684\u590d\u4e60\uff0c\u6c34\u5e73\u5df2\u7ecf\u6709\u4e86\u4e00\u4e2a\u8f83\u5927\u7684\u63d0\u5347\uff0c\u4f46\u662f\u8003\u751f\u8981\u771f\u6b63\u6210\u4e3a\u201c\u8003\u8bd5\u8fbe\u4eba\u201d\uff0c\u8fd8\u5fc5\u987b\u5728\u77ed\u677f\u4e0a\u4e0b\u5de5\u592b\uff0c\u9488\u5bf9\u81ea\u5df1\u7684\u4e0d\u8db3\u8fdb\u884c\u4e13\u9879\u7a81\u7834\uff0c\u6bd4\u5982\u6709\u7684\u8003\u751f\u6570\u5b66\u8fd0\u7b97\u8f83\u5dee\uff0c\u4e00\u76f4\u96be\u4ee5\u63d0\u9ad8\uff0c\u8fd9\u4e2a\u65f6\u5019\u5343\u4e07\u4e0d\u80fd\u653e\u5f03\uff0c\u8003\u751f\u53ef\u4ee5\u901a\u8fc7\u4e13\u9879\u590d\u4e60\uff0c\u653b\u514b\u77ed\u677f\uff0c\u5b9e\u73b0\u89e3\u9898\u80fd\u529b\u7684\u63d0\u9ad8\u3002
\uff081\uff09\u8003\u751f\u8981\u5bf9\u4e13\u9879\u4e2d\u6bcf\u4e00\u79cd\u9898\u578b\u505a\u5168\u9762\u3001\u7ec6\u81f4\u7684\u638c\u63e1\uff0c\u5c24\u5176\u5bf9\u8bd5\u9898\u7279\u70b9\u4e0e\u7b54\u9898\u89c4\u5f8b\u548c\u65b9\u6cd5\u8ba4\u771f\u5730\u5b66\u4e60\uff0c\u8fd9\u662f\u4e00\u4e2a\u91cd\u8981\u6b65\u9aa4\u3002
\uff082\uff09\u901a\u8fc7\u505a\u7ec3\u4e60\u6765\u5de9\u56fa\u81ea\u5df1\u638c\u63e1\u7684\u9898\u578b\u548c\u89e3\u9898\u6280\u5de7\uff0c\u901a\u8fc7\u4e0d\u65ad\u7684\u7ec3\u4e60\u5b9e\u8df5\u6765\u603b\u7ed3\u51fa\u81ea\u5df1\u7684\u7b54\u9898\u7ecf\u9a8c\uff0c\u4fdd\u8bc1\u81ea\u5df1\u7684\u7b54\u9898\u65b9\u6cd5\u65e2\u7701\u65f6\u95f4\u53c8\u6709\u6b63\u786e\u7387\u3002
\uff083\uff09\u5bf9\u6613\u9519\u9898\u3001\u96be\u9898\u8fdb\u884c\u6807\u6ce8\uff0c\u4e0b\u6b21\u7740\u91cd\u590d\u4e60\u3002
3\u3001\u6a21\u62df\u7ec3\u4e60\uff0c\u6700\u540e\u51b2\u523a\u8d8a\u662f\u4e34\u8fd1\u8003\u8bd5\uff0c\u8003\u751f\u8d8a\u662f\u4e0d\u80fd\u653e\u677e\u6a21\u62df\u7ec3\u4e60\uff0c\u4ee5\u514d\u8003\u8bd5\u65f6\u56e0\u751f\u758f\u800c\u9020\u6210\u7684\u7d27\u5f20\u3001\u7b54\u9898\u901f\u5ea6\u4e0b\u964d\u7684\u60c5\u51b5\u53d1\u751f\u3002\u5728\u8003\u524d\u4e00\u4e2a\u6708\u5728\u6309\u90e8\u5c31\u73ed\u5b9e\u884c\u65e5\u5e38\u590d\u4e60\u8ba1\u5212\u7684\u540c\u65f6\uff0c\u4e2d.\u516c\u6559\u80b2\u4e13\u5bb6\u5efa\u8bae\u8003\u751f\u53ef\u91c7\u7528\u5b9e\u6218\u6a21\u8003\u6a21\u5f0f\u8fdb\u884c\u590d\u4e60\uff0c\u5373\u5c06\u81ea\u5df1\u7684\u4f5c\u7b54\u65f6\u95f4\u8c03\u6574\u5230\u4e0e\u516c\u52a1\u5458\u884c\u6d4b\u8003\u8bd5\u7684\u65f6\u95f4(\u4e0a\u53489\uff1a00\u201411\uff1a00)\u4e00\u81f4\uff0c\u4ee5\u57f9\u517b\u601d\u7ef4\u7684\u654f\u611f\u5ea6\uff0c\u5feb\u901f\u9002\u5e94\u771f\u8003\u73af\u5883\u3002
\u4e25\u683c\u6309\u7167\u8003\u8bd5\u7684\u65f6\u95f4\u5b89\u6392\u8fdb\u884c\u5b9e\u6218\u6a21\u8003\uff0c\u53ef\u4ee5\u63d0\u524d\u9002\u5e94\u8003\u573a\u6c14\u6c1b\u548c\u8003\u8bd5\u8282\u594f\uff0c\u6709\u5229\u4e8e\u638c\u63e1\u7b54\u9898\u65f6\u95f4\uff0c\u65e2\u6d88\u9664\u4e86\u8003\u751f\u5728\u8003\u573a\u4e2d\u7531\u4e8e\u65f6\u95f4\u63a7\u5236\u4e0d\u597d\u9020\u6210\u7684\u7d27\u5f20\u60c5\u7eea\uff0c\u4e5f\u53ef\u4ee5\u8ba9\u8003\u751f\u53ca\u65f6\u53d1\u73b0\u81ea\u5df1\u5728\u5b9e\u6218\u4e2d\u53ef\u80fd\u4f1a\u5931\u5229\u7684\u5730\u65b9\uff0c\u53ca\u65e9\u505a\u597d\u5e94\u5bf9\u3002
\u5982\u6709\u7591\u95ee\uff0c\u6b22\u8fce\u5411\u4e2d\u516c\u6559\u80b2\u4f01\u4e1a\u77e5\u9053\u63d0\u95ee\u3002
=38-29
=9（人）
21+17-29=38-29=9
(21＋17)－29=9人
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绛旓細42+29-50=21浜 ~婊℃剰杩樻湜閲囩撼~~璋㈣阿~o(锔讹缚锔)o
绛旓細鑰佸笀鍑轰袱閬撻,鍦50鍚嶅悓瀛﹀仛瀵圭涓棰樼殑鏈26浜,鍋氬绗浜岄鐨鏈29浜,骞朵笖杩樺彂鐜版瘡浣嶅悓瀛﹁嚦灏戝仛瀵逛竴閬撻.涓ら亾棰橀兘鍋氬鐨勬湁澶氬皯浜?锛26+29锛-50=5
绛旓細绗竴閬撻敊鐨勬湁50-26=24浜猴紝鍥犱负娌℃湁涓ら亾閮介敊鐨勶紝閭ｄ箞29浜閲岄潰鑲畾鏈24浜烘槸鍙鐨勭浜岄亾锛鎵浠ヤ袱閬撻兘姝ｇ‘鐨勫氨鍙湁29-24=5浜恒
绛旓細鈭垫瘡浣嶅悓瀛﹁嚦灏戝仛瀵逛竴閬撻 鈭村彧鍋氬绗浜岄鐨勫悓瀛︿负 50-42=8浜 鍙仛瀵圭涓棰樼殑鍚屽鏁颁负 50-29=21浜 鍒涓ら閮藉鐨勪负 50-21-8=21浜
绛旓細寰堝ソ鍋氬晩锛屽氨鏄涓閬撶瓟瀵圭殑鍔犱笂绗浜岄亾绛斿鐨勫啀鍑忓幓鐝笂鐨勬讳汉鏁帮紝鍗24+29-36=14銆傚師鍥犳槸寰堢畝鍗曪紝鍥犱负涓ら亾绛斿鐨勯浜烘暟鐩稿姞浼氭妸閮界瓟瀵圭殑浜烘暟澶氬姞浜嗕竴鍊嶏紝瓒呭嚭鎬讳汉鏁板氨鏄鍔犵殑閭ｄ竴鍊嶄篃灏辨槸閮界瓟瀵圭殑
绛旓細浣犲ソ 浣犲彲浠ョ敾鍥炬潵瑙ｏ紝鎴戣繖閲岃涓涓嬫濊矾锛岀涓棰樻湁24浜虹瓟瀵癸紝绗浜岄鏈29浜绛斿锛岄偅涔24+29=53锛53浜轰腑鍖呮嫭浜嗙瓟瀵圭涓棰樼殑浜哄拰绛斿绗簩棰樼殑浜猴紝涔熷寘鍚簡绛斿涓ら亾棰鐨勪汉锛堝姞浜嗕袱閬嶏級鎵浠53-36=17灏辨槸涓ら亾棰橀兘绛斿鐨勪汉銆傛渶鍚庣殑绛旀鏄17浜恒傚笇鏈涜兘甯埌浣狅紒鏈夐棶棰樺彲浠ヨ拷闂紒鏄庣櫧浜嗙殑璇濊閲囩撼~~ ...
绛旓細21-(30-18)=21-12 =9
绛旓細鍐嶆嬁53-36=17锛堜汉锛夊嵆鍙緱鍑虹瓟妗堛傚師鍥犳槸绗竴鍜岀浜岄閮藉仛瀵硅呭湪鍗曚綔瀵圭涓棰樼殑浜烘暟鍜屽崟浣滃绗簩棰樿呯殑浜烘暟閲岄兘鏈夌涓鍜岀浜岄閮藉仛瀵硅咃紝鍥犱负浠栦滑鍦ㄤ汉鏁颁腑閲嶅浜嗭紝鎵浠ヤ細姣36浜哄锛屾墍浠ユ嬁53-36=17锛堜汉锛夋潵寰楀嚭閲嶅鐨勭殑浜恒傚洜涓洪噸澶嶇殑浜哄氨鏄涓鍜岀浜岄閮藉仛瀵硅咃紝鎵浠17浜烘槸涓ら亾棰閮藉仛...
绛旓細鑰佸笀鍑轰簡涓ら亾鏁板棰橈紝鍦40浜轰腑鍋氬绗竴棰樼殑鏈31浜猴紝鍋氬绗浜岄鐨勬湁28浜猴紝涓ら亾棰橀兘鍋氬鐨勬湁10浜恒傛牴鎹鎰忓垪绠楀紡锛(31+28)-40 =59-19 =19 鎵浠ヤ袱閬撻閮藉仛瀵圭殑鏈10浜 娣峰悎杩愮畻锛氬鏋滀竴绾ц繍绠楀拰浜岀骇杩愮畻锛屽悓鏃舵湁锛屽厛绠椾簩绾ц繍绠椼傚鏋滀竴绾э紝浜岀骇锛屼笁绾ц繍绠楋紙鍗充箻鏂广佸紑鏂瑰拰瀵规暟杩愮畻锛夊悓鏃舵湁...
绛旓細42+29=71 鍏卞仛瀵71閬撻鐩 71-50=21 棰樼洰鏁-浜烘暟=鍋氬2閬撻鐨勪汉鏁般
