有含盐为10%的盐水300克,要配制含盐率8%,要加水多少克?过程!!好评!!求解!!大神!!快快
\u6709\u542b\u76d0\u4e3a10%\u7684\u76d0\u6c34300\u514b\uff0c\u8981\u914d\u5236\u542b\u76d0\u73878%\uff0c\u8981\u52a0\u6c34\u591a\u5c11\u514b\uff1f\u3010\u5206\u6790\u3011
\u2460\u89e3\u7b54\u6b64\u6d53\u5ea6\u95ee\u9898\u8981\u5f04\u6e05\u4e0b\u5217\u5173\u7cfb\u5f0f\uff1a\u6eb6\u6db2\u91cd\u91cf\u00d7\u6d53\u5ea6=\u6eb6\u8d28\u91cd\u91cf\uff0c\u6eb6\u8d28\u91cd\u91cf\u00f7\u6d53\u5ea6=\u6eb6\u6db2\u91cd\u91cf\uff1b
\u2461\u76d0\u6c34\u7684\u91cd\u91cf\u662f300\u514b\uff0c\u6d53\u5ea6\u4e3a10%\uff0c\u5176\u4e2d\u542b\u76d0\u91cf=300\u00d710%=30(\u514b)\uff1b\u52a0\u6c34\u540e\uff0c\u542b\u76d0\u91cf\u4e0d\u53d8\uff0c\u4e5f\u5c31\u662f\u5728\u7a00\u91ca\u540e\u6d53\u5ea6\u4e3a4%\u7684\u76d0\u6c34\u4e2d\uff0c\u542b\u76d0\u91cf\u4ecd\u4e3a30\u514b\uff1b\u53ef\u77e5\uff0c\u7a00\u91ca\u540e\u7684\u76d0\u6c34\u91cd\u91cf\u4e3a30\u00f74%=750(\u514b)\uff1b\u539f\u6765300\u514b\u7684\u76d0\u6c34\uff0c\u52a0\u6c34\u540e\u53d8\u4e3a750\u514b\uff0c\u6240\u4ee5\uff0c\u52a0\u5165\u7684\u6c34\u4f4d750-300=450\uff08\u514b\uff09\u3002
\u3010\u89e3\u7b54\u3011
\u89e3\uff1a
\u9700\u8981\u52a0\u6c34\u7684\u91cd\u91cf
=300\u00d710%\u00f74%-300
=30\u00f74%-300
=750-300
=450\uff08\u514b\uff09\u7b54\uff1a\u9700\u8981\u52a0\u6c34300\u514b\u3002
\u8bbe\u52a0\u6c34Xg\u8fd9\u7b49\u5f0f50x15%=(X+50)x10%\u89e3\u5f97X=25
解设加水x克因为盐不变
所以300*10%=(300+x)*8%
30=24+0.08x
6=0.08x
x=75
所以加水75克
绛旓細鈶$洂姘寸殑閲嶉噺鏄300鍏嬶紝娴撳害涓10%锛屽叾涓鍚洂閲=300脳10%=30(鍏)锛涘姞姘村悗锛屽惈鐩愰噺涓嶅彉锛屼篃灏辨槸鍦ㄧ█閲婂悗娴撳害涓4%鐨勭洂姘涓紝鍚洂閲忎粛涓30鍏嬶紱鍙煡锛岀█閲婂悗鐨勭洂姘撮噸閲忎负30梅4%=750(鍏)锛涘師鏉300鍏嬬殑鐩愭按锛屽姞姘村悗鍙樹负750鍏嬶紝鎵浠ワ紝鍔犲叆鐨勬按浣750-300=450锛堝厠锛夈傘愯В绛斻戣В锛氶渶瑕佸姞姘寸殑閲嶉噺 =...
绛旓細瑙h鍔犳按x鍏 鍥犱负鐩愪笉鍙 鎵浠300*10%=锛300+x锛*8 30=24+0.08x 6=0.08x x=75 鎵浠ュ姞姘75鍏
绛旓細鈶$洂姘寸殑閲嶉噺鏄300鍏嬶紝娴撳害涓10%锛屽叾涓鍚洂閲=300脳10%=30(鍏)锛涘姞姘村悗锛屽惈鐩愰噺涓嶅彉锛屼篃灏辨槸鍦ㄧ█閲婂悗娴撳害涓4%鐨勭洂姘涓紝鍚洂閲忎粛涓30鍏嬶紱鍙煡锛岀█閲婂悗鐨勭洂姘撮噸閲忎负30梅4%=750(鍏)锛涘師鏉300鍏嬬殑鐩愭按锛屽姞姘村悗鍙樹负750鍏嬶紝鎵浠ワ紝鍔犲叆鐨勬按浣750-300=450锛堝厠锛夈傘愯В绛斻戣В锛氶渶瑕佸姞姘寸殑閲嶉噺 =...
绛旓細300鍏嬬殑姘村惈鐩=300g脳10%=30g 30g梅4%=750g 鍔犲叆=750g-300g=450g
绛旓細鐩愶細300*10%=30鍏 姘达細300-30=270鍏 鍚洂25%鐨勬憾娑蹭腑姘村惈鐜囷細1-25%=75 鏂扮殑鐩愭按锛270/75%=270/0.75=360鍏 鐩愶細360*25%=90鍏 鍔犵洂锛90-30=60鍏 绛旓細鍔犱簡鐩60鍏嬨
绛旓細鐧惧垎涔嬪崄鐨勭洂姘翠笁鐧惧厠锛瀹為檯鍚洂10锛脳30鍏嬶紳3鍏嬶紝鎵浠ヨ浣垮惈鐩愮巼杈惧埌鐧惧垎涔嬩簩鍗侀渶鍔3鍏嬬洂銆
绛旓細璁句负x锛 锛300*10%+x锛/锛300+x锛=20%锛屾眰鐨剎=75
绛旓細鐩愭槸300脳10%=30鍏 鎵浠5%鐨勭洂姘鏄30梅5%=600鍏 600-300=300 绛旓細闇瑕佸姞姘300鍏
绛旓細娣峰悎鍚庣殑娴撳害=娣峰悎鍚庣殑鎬绘憾璐/娣峰悎鍚庣殑鎬绘憾娑=锛10%*300+15%*200锛/(200+300)=60/500=12
绛旓細璁剧洰鍓鐩鏈塜鍏 x/(300-X)=10 鎵浠=300/11 瑕佸姞鍏鍏 (300/11+Y)/(300+Y)=0.46 鎵浠=205.05鍏