ldcf.net
当前位置:首页 >> 7+A/(x%4)=(3%x)/(4%x) >>

7+A/(x%4)=(3%x)/(4%x)

0x+36.4%x+27.3%x+72.7%x+86.4%x =1 x=5/1114 所以,a=0 b=(5/1114)×36.4%≈16.34% c=(5/1114)×27.3%≈12.25% d=(5/1114)×72.7%≈32.63% e=(5/1114)×86.4%≈38.78%

(1)设要变成含碘4%的碘酒,要加碘x克,可得:240×3%+x240+x=4% 7.2+x240+x=4%, 7.2+x=(240+x)×4%, 7.2+x=9.6+4%x, 96%x=2.4, x=2.5答:变成含碘4%的碘酒,要加碘2.5克.(2)设可蒸发掉酒精x克, 240×3%240?x=4%. (240-x)×4%=7.2, 9...

画出其正态密度曲线图,观察图得P(6<ξ<8)=12[P(2≤ξ≤8)-P(4≤ξ≤6)]=12[P(μ-3σ<ξ<μ+3σ)-P(μ-σ<ξ<μ+σ)]=12(0.997-0.683)=0.157,故答案为:0.157

设甲x 千克 乙y千克 (12%x+3%y) /(x+y)>=4% (2%x+4%y) /(x+y)>=3% (3%x+15%y) /(x+y)>=5% 成本z=(3x+2y)/(x+y) 前三...

X-X×0.03×1.1=4499.99 X-0.033X=4499.99 0.967X=4499.99 X=4499.99÷0.967 X=4653.56

5000x4x(1-3%) =20000x97% =200x97 =19400

3.4%=3%+0.4% 还是乘法分配律啊 3321×3.4%=3321×(3%+0.4%)=3321×3%+3321×0.4%

解答:由每方水泥用量为250kg,得到每方砂的含量为:250*2.5=625kg,每方碎石的含量为:250*4=1000kg,每方水的含量为:250*0.6=150kg,根据含水量换算施工配合比:施工中每方砂的含量为:250*2.5*1.01=631kg,每方碎石的含量为:250*4*1.03=103...

http://www.toodou.com/search/programs/?kw=%D5%D4%DE%B1+%C2%B3%D4%A5%D3%D0%D4%BC&nav_search_target=0&nav_search_submit.x=10&nav_...

x=1.7g所以稀释后的H2O2溶液中溶质的质量分数为: 1.7g 50g ×100%=3.4%...2015-02-04 某课外学习小组将30%的H2O2溶液稀释为3%后,用来制取氧... 4 ...

网站首页 | 网站地图
All rights reserved Powered by www.ldcf.net
copyright ©right 2010-2021。
内容来自网络,如有侵犯请联系客服。zhit325@qq.com