七年级一班有54人,男生的人数比女生的人数的2倍少6人.女生有多少人? 2倍少7人，女生有多少人
\u4e941\u73ed\u5171\u670954\u4eba\uff0c\u5176\u4e2d\u7537\u751f\u4eba\u6570\u6bd4\u5973\u751f\u4eba\u6570\u76842\u500d\u8fd8\u591a3\u4eba\uff0c\u4e94\u4e00\u73ed\u7537\uff0c\u5973\u751f\u5404\u6709\u591a\u5c11\u4eba?\u8bbe\u5973\u6709X\u4eba\uff0c\u5219\u7537\u751f\u6709\uff0854-x\uff09\u4eba
2x+3=54-x
x=17
54-x=37
\u7b54\uff1a\u4e94\u4e00\u73ed\u5973\u751f\u670917\u4eba\u7537\u751f\u670937\u4eba.
\u9898\u76ee\uff1a\u4e09\u5e74(3)\u73ed\u5171\u6709\u5b66\u751f62\u4eba,\u7537\u751f\u7684\u4eba\u6570\u6bd4\u5973\u751f\u76842\u500d\u5c117\u4eba,\u5973\u751f\u6709\u591a\u5c11\u4eba\uff1f
\u89e3\uff1a\u8bbe\u5973\u751f\u6709x\u4eba\uff0c\u7537\u751f\u67092x-7\u4eba\uff0c
2x-7+x=62
3x-7=62
3x=62+7
3x=69
x=69\u00f73
x=23
\u7b54\uff1a\u5973\u751f\u670923\u4eba\u3002
20 （54+6）/3
20
绛旓細璁惧コ鐢熺殑浜烘暟涓簒浜猴紝鍒鐢风敓鐨勪汉鏁琛ㄧず涓2x-6 2x-6+x=54 x=20
绛旓細鈭靛叏鐝汉鏁颁负54浜恒傚垯4/5x+x=54 寰梮涓30 鈭寸敺鐢熶汉鏁颁负30浜銆
绛旓細绛:璇ョ彮鏈夌敺鐢33浜锛屽コ鐢21浜恒
绛旓細璁惧コ鐢焁鍙 2X+X=54 3X=54 X=54梅3 X=18 鐢风敓=18*2=36鍙 涓嶆噦鍙拷闂紝鏈夊府鍔╄閲囩撼锛岃阿璋紒
绛旓細54脳4锛9锛24浜 54-24锛30浜 绛旓細鐢风敓鏈24浜锛屽コ鐢熸湁30浜
绛旓細鐢峰コ鐢熼棶棰橈細璁鐢风敓鏄疿锛屽垯濂崇敓鏄4/5X锛屽垯鍏ㄧ彮涓篨+4/5X=54浜猴紝瑙ｅ緱X=30锛屽垯鐢风敓30浜猴紝濂崇敓24浜 缁冲瓙闂锛氳缁跨怀闀縓绫筹紝鍒欒摑缁虫瘮缁跨怀闀2/5锛屼笖闀3/4绫筹紝鍒2/5X=3/4绫 瑙ｅ緱X=15/8绫筹紝鍒欑豢缁抽暱15/8绫
绛旓細鎴戜滑鍙互鎶婄彮绾鐨勪汉鏁鐪嬫垚鍗曚綅涓銆傜敺鐢熷崰5|9锛岄偅涔堝コ鐢熷氨鏄崰锛1-5|9=4|9.鑷充簬姹傜敺鐢熷拰濂崇敓鍚勬湁澶氬皯浜恒傛垜浠彧瑕佸皢浠栦滑鍗犲緱鍒嗘暟涔樹互鎬讳汉鏁板氨鍙互浜嗐傜敺鐢熸湁锛54脳5|9=30锛堜汉锛夊コ鐢熸湁锛54-30=24锛堜汉锛夌瓟锛氬コ鐢熷崰4|9锛岀敺鐢鏈30浜猴紝濂崇敓鏈24浜恒傚簲璇ュ氨鏄繖鏍蜂簡锛屽笇鏈涙垜鐨勫洖绛旇兘缁欎綘甯︽潵涓浜...
绛旓細30鐢风敓锛24濂崇敓銆傝繖棰樺緢绠鍗曪紝54涓汉锛閭ｅコ姣斾緥鏄5锛4锛岄偅涔堜綘灏辨妸浜哄垎鎴5+4=9浠姐備竴浠藉氨鏄54梅9=6浜猴紝閭ｄ箞鐢风敓灏6x5=30浜猴紝濂崇敓6x4=24浜
绛旓細璁撅細濂崇敓鏈5X浜猴紝鐢风敓鏈4X浜 5X锛4X锛54 X锛6 鎵浠ワ紝4X锛24 绛旓細鐢风敓鏈24浜
绛旓細1/4 x = 1/5 (54-x)瑙ｆ柟绋嬪緱x=36 鐢风敓36浜猴紝濂崇敓18浜恒
