国家质量标准规定:市售尿素CO(NH2)2的质量分数在96%以上为达标一级品,县供销社出售1t尿素,其中含氮元素的质量为0.44t(杂质不含氮),通过计算说明这吨尿素是不是一级品?(e(|2x(w-I0t2S8f
解:设含氮元素质量为0.44t的尿素质量为x(e(|2x(w-I0t2S8f
~2N(e(|2x(w-I0t2S8f
60 28(e(|2x(w-I0t2S8f
x 0.44t(e(|2x(w-I0t2S8f
(e(|2x(w-I0t2S8f
94.3%<96%(e(|2x(w-I0t2S8f
答:这吨尿素不是7V4C*~4`3U9~'Q1S7w。(e(|2x(w-I0t2S8f