求助啊~，三道prep Data sufficient 题做错了，求正确的思路？谢谢

Davewsy

1. of the 60 aniamls on a certain farm, 2/3 are either pigs or cows. How many of the animals are cow.
    (1) the farm has more than twice as many cows as it has pigs.
    (2) the farm has more than 12 pigs.

2. Are as least 10 percent of the people in country X who are 65 years old or older employed?
    (1) In the country X, 11.3 percent of the population is 65 years older.
    (2) In the country X, of the populaiton 65 years old or older, 20 percent of the men and 10 percent of the women are employed.

3. If x is a positive number less than 10, is z greater than the average  of x and 10?
  (1) on the number line, z is closer to 10 than it is to x.
  (2) z=5x

第一遍我做错了以后，自己又做了一遍，还是和答案不一样，求各位大牛帮忙，给一个正确的思路？

ahhxzq

说下第一题吧，我也做错过，条件1中more than twice as many cows as it has pigs：c>2p,
且题目指出c+p=60*2/3=40.
所以3p<40.结合条件2：p>12
所以p=13

cmazhaoyu

第二题是这样的，题目问你是不是至少65岁的人里有10%被雇佣
选项（2）中，65岁以上20%男性和10%女性都被雇佣了（不存在不男不女的人妖），所以肯定能确定有多于10%的65岁以上人氏被雇佣了，所以选B，这题很阴险啊~~我也错了

cola5117

第三题的话，找几个数字举下反例
我认为第一个条件应该是满足的，这样的话， Z就大于X和10的平均数了
第二个条件，比如说x=0.5 那么Z=2.5 这个时候2.5< 0.5（0.5+10）
如果X=2 那么 Z=10 且 10>0.5(10+2)
所以选A ? correct me if i'm wrong