设购大桶涂料x桶,小桶y桶.18x+10y=330,y=(330-18x)/10需要钱数为 m=176.4x+100y=176.4x+100(330-18x)/10就是 m=3300-3.6x (1)y=(330-18x)/10=33-9x/5 (2)从(1)知购大桶越多越省钱,从(2)可看出当x=5,10,15时y有正整数...