下周二就要考试了，今天模拟数学错了好多啊，求教几道数学题

AbbyShuai

1. A certain city with a population of 132000 is to be divided into 11 voting districts, and no district is to have a population that is more than 10% greater than any other district.What is the minimum possible population that the least populated district could have? A10700 B10800 C10900 D11000 E11010 (虽然我做正确了但是不知道思路对不对求大牛给过程)

2.Before being simplified, the instructions for computing income tax in Country R were to add 2% of one's annual income to the average (arithmatic mean) of 100 units of Country R's currency and 1 percent of one's annual income. Which of the following represents the simplified formula for computing the income tax, in Country R's currency, for a person in that country whose annual income is I. 答案是50+I/40(求翻译高亮部分 并且给出过程啊)

坐等牛牛们！！！拜托啊

AbbyShuai

竹迹 发表于 2013-8-31 23:15
额，和楼上列的式子是一样的，不过我的解释跟不大一样。
no district is to have a population that is mo ...

谢啦谢啦 终于明白了

AbbyShuai

zhouchenqi2013 发表于 2013-8-31 23:05
要让最小的那一个最大，就要让另外十个同时最小。由于集合中任意一个数不能大于集合中其他数的10%，所以其 ...

理解了。。谢谢啦

竹迹

额，和楼上列的式子是一样的，不过我的解释跟不大一样。
no district is to have a population that is more than 10% greater than any other district这句话就意味着最大的那个也只能比最小的那个多10%
题目要求最小的那个x尽量小，也就等同于剩下的10个每个都尽量大即都是最大的1.1x
式子见楼上

zhouchenqi2013

要让最小的那一个最大，就要让另外十个同时最小。由于集合中任意一个数不能大于集合中其他数的10%，所以其他十个数均为最小数的110%。假设最小的是X，其他十个是1.1X，那么求和就是X+10*1.1X=12X=132000，X=11000

AbbyShuai

竹迹 发表于 2013-8-31 21:22
1.选D吧？假设其他10个区人数尽量大
2.R国的个人所得税=个人年收入的2%+个人收入1%与100单位R国货币的平均 ...

谢谢啊 第二题理解了 但是第一题可不可以详细一点？ 怎么使其他10个区人数尽量大？

竹迹

1.选D吧？假设其他10个区人数尽量大
2.R国的个人所得税=个人年收入的2%+个人收入1%与100单位R国货币的平均值
答案：个人所得税=2%I+（1%I+100）/2

额，应该就是这样