→ qqopqqop:感激 09/02 19:15
※ 引述《qqopqqop (p )》之銘言：
: A certain company that sells only cars and trucks reported that
: revenues from car sales in 1997 were down 11 percent from 1996 and revenues
: from truck sales in 1997 were up 7 percent from 1996. If total revenues
: from car sales and truck sales in 1997 were up 1 percent from 1996, what is
: the ratio of revenue from car sales in 1996 to revenue from truck sales in
: 1996?
: ans 1:2
: 怎麼算怎麼不對 有人可以幫我一下嗎><?
依題意可以列三個方程式
1. 1996 car sales* 0.89= 1997 car sales
2. 1996 truck sales* 1.07= 1997 truck sales
將 1 2 代入 3
3. (1996 car sales + 1996 truck sales)* 1.01= 1997 car sales + 1997 truck sales
= 0.89(1996 car sales)+1.07(97 Trk sales)
把方程式3移過來移過去 過程就不贅述了
可得 0.12(1996 car sales )= 0.06( 1996 truck sales)
故 ratio C:T= 1:2
大概就是這樣 希望有幫助到你!
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◆ From: 220.133.8.80
※ 編輯: dodohuang 來自: 220.133.8.80 (09/01 22:18)
※ 編輯: dodohuang 來自: 220.133.8.80 (09/01 22:18)