请君饮用纯净水 华东师大版八年级

• 作 者: 周以宏
• 机 构: 江苏省苏州中学,
• 出 处: 中学数学教学参考
• 发表日期: 2006年Z2期
• 关键词: 桶装纯净水 饮用纯净水 学生集体 其他费用 销售价 市场调查 已知信息 函数关系式 育人意识 数形结合

【题目】晨曦中学八年级(1)班共有学生50人,据统计,原来每人每年用于购买饮料的平均支出是 a 元.经测算和市场调查,若该班学生集体改饮某品牌的桶装纯净水,则年总费用由两部分组成,一部分是购买纯净水的费用,另一部分是其他费用780元.其中,纯净水的销售价 x(元/桶)与年购买总量 y(桶)之间满足如图8所示的关系.

[Title] Dawn Middle School eighth grade (1) class a total of 50 students, according to statistics, the average per person per year for the purchase of drinks is a yuan .According to the calculation and market research, if the class students collectively to drink a brand Bottled pure water, then the total annual cost of two parts, part of the cost of purchasing pure water, and the other part of the other costs 780. Among them, the sales price of pure water x (yuan / barrel) and the total annual purchase y ( Barrel) to satisfy the relationship shown in Figure 8.