请问2道prep的数学题~~

dbearwanger

a certain city with a population of 132,000 is to be devided into 11 voting districts, and no district is to have a population that is more than 10 percent greater than the population of any other district. What is the minimum possible population that the least populated district could have?
10,700
10,800
10,900
11,000
11,100

答案是d

If x, y and z are intergers and xy+z is an odd interger, is x an even integer?
1. xy+xz is an even integer
2. y + xz is an odd integer

答案是a

大家圣诞快乐哦~~

dbearwanger

thanks  a   lot !!!!

missdandan

QUOTE:

a certain city with a population of 132,000 is to be devided into 11 voting districts, and no district is to have a population that is more than 10 percent greater than the population of any other district. What is the minimum possible population that the least populated district could have?
10,700
10,800
10,900
11,000
11,100

答案是d

最小的那个是一个最小的,10个比最小的大10%的

If x, y and z are intergers and xy+z is an odd interger, is x an even integer?
1. xy+xz is an even integer
2. y + xz is an odd integer

答案是a

两个相减z(x-1)奇数,两个都是奇数,所以知道x偶数

QUOTE:

相减(x-1)(y-z)偶数,不能确定