作者officium (officium)
看板GRE_Verbal
标题Re: [问题]请问来欣的数学问题 M8 :)
时间Sun Jun 3 16:43:49 2007
太谢谢你了
不过我搞不太懂第17
我老是弄不清楚那个those 哪个时候指原本的全部人
哪个时候指某依部分的人呢
我以前都是看those跟在谁後面就是指谁
可是 为什麽这题是指全部人
※ 引述《tingting88 (啊哈哈哈哈哈哈哈)》之铭言：
: ※ 引述《officium (officium)》之铭言：
: : M8
: : 17
: : In a nationwide poll, N people were interviewed.
: : If 1/4 of them answered ”Yes” to Q1,
: : and of those, 1/3 answered “Yes” to Q2,
: : which of the following expressions
: : represents the number of people interviewed who
: : did not answer “Yes” to both Q?
: 他的意思应该是1/4的人在Q1回答yes,然後这些人当中又有1/3的人在Q2回答yes
: 最後他问有多少人没有两题都回答yes,所以答案应该是 N*(1-(1/4)*(1/3))=11N/12
: : 30
: : The organizers of a fair projected a 25% increase in
: : attendance this year over
: : that of last year, but attendance this year actually decrease by 20%.
: : What percent of the projected attendance was the actual attendance?
: 假设去年的出席率是x 假设的是1.25x 实际的是0.8x
: 他问的是 0.8x/1.25x=64% (其实我也看不太懂题目,是照答案推的=.=)
: : 22
: : A hiker walked for 2 days, On the second day the hiker walked
: : 2 hours longer and at an average speed 1 mile per hour faster
: : than he walked on the first day. IF during the two days he walked
: : a total of 64 miles and spent a total of 18 hrs walking, what
: : was his average speed on the first day
: : 我设第一天走 x小时 所以第二天 x+2
: : 2x+2=18 x=8
: 到这边没问题 接着假设第一天的平均速率是v 所以第二天的是v+1
: v*8+(v+1)*10=18v+10=64 v=3
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◆ From: 59.117.100.93
1F：推 tingting88:those是指那1/4的人吧 140.112.4.249 06/03 16:56
2F：推 officium:我了了我做了什麽蠢事 :P 61.217.226.130 06/05 09:01
3F：→ officium:谢谢你欸 :) 61.217.226.130 06/05 09:02