PREP1模考的一道数学题·~求解答~

queenie924

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

答案是C 对于 The farm has more than twice as many cows as it has pigs 不是太理解~做语法做多了··看的就想改错····

求NN详细解答下~

queenie924

顶上去·

wenjie87

cows比pigs的2倍还多

wenjie87

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

答案是C 对于 The farm has more than twice as many cows as it has pigs 不是太理解~做语法做多了··看的就想改错····

求NN详细解答下~

-- by 会员 queenie924 (2010/8/22 17:45:11)

       （1）cows>2*pigs
       当pigs等于13的时候，cows等于27，成立、
       当Pigs等于12，cows等于26，也成立
       所以无法确定
     （2）只知道pigs>12，无法确定cows
（1）+（2），可知道Pigs只能为13

queenie924

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

答案是C 对于 The farm has more than twice as many cows as it has pigs 不是太理解~做语法做多了··看的就想改错····

求NN详细解答下~

-- by 会员 queenie924 (2010/8/22 17:45:11)

谢谢啦~



       （1）cows>2*pigs
       当pigs等于13的时候，cows等于27，成立、
       当Pigs等于12，cows等于26，也成立
       所以无法确定
     （2）只知道pigs>12，无法确定cows
（1）+（2），可知道Pigs只能为13

-- by 会员 wenjie87 (2010/8/22 20:26:14)

谢谢啦~