Re: [計量] 請教 PP2 test1 一題圖表題

[Dontco (東摳)]

※ 引述《addison1001 (小歐)》之銘言：
: PP2 test one 有一題計量的圖表題
: 借一下"whereright (需要放空...)"網友的圖
: http://photo.xuite.net/happyeverydaay/5218184/1.jpg
: 第三題中問到
: If each of the average rating was the arimetic mean of rating given by
: the 100 travel agents, approximately how much greater was total of the ratings
: given to all three airlines for reliability than that for promptness?
: A)25 B)50 C)125 D)250 E)500
: 可以請問一下這題在問什麼嗎?
: 要怎麼算?
: 非常感謝


借這邊問一下

原文放的這個圖 我也不會 有神人能幫我解釋嗎?

http://photo.xuite.net/happyeverydaay/5218184/1.jpg



敘述題..

http://ppt.cc/LmL2

A developer has land that has X feet of lake frontage. The land is to be
subdivided into lots, each of which is to have either feet or 100 feet of
lake frontage. if 1/9 of the lots are to have 80 feet of frontage each and
remaining 40 lots are to have 100 feet of frontage each, what is the value of
x?

A 400  B 3200  C 3700  D 4400  E 4760






最後是這題比大小

http://ppt.cc/9bsV




有神人能幫我解答嗎?  謝謝


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◆ From: 1.171.52.75
推 chen52      :第二題也看不太懂but我是想成 長方形parking lots
→ chen52      :40是 8/9 so 1/9 is  40/8
→ chen52      :therefore, x=80*40/8+40*100=4400
→ chen52      :答案我記得是D 沒有特別去查 @@ 有錯麻煩指教一下
推 chen52      :最後一題 去查一下OG range,mode 的定義 很簡單常考
→ chen52      :range=x^2-1=4 so x>2
→ tonychung   :1. C的總和最少，再看左邊C是第一名的佔多少