作者nehsband (bibo)
看板GRE_Verbal
標題Re: [計量] 請教來欣數學M3~
時間Sun Sep 30 22:28:39 2007
※ 引述《whisperheart (mione  N )》之銘言:
: 1. A tourist purchased a total of $1500 worth of traveler's check in $10
: and $50 denominations. During the trip the tourist casehed 7 checks and then
: lost all of the rest. If the number of $10 checks cashed was one more or
: one less that the number of $50 checks cashed, what is the minimum possible
: value of the checks that were lost?
: (A) $1430
: (B) $1310
: (C) $1290
: (D) $1270
: (E) $1150 答案是D
假設消耗的七張check中,有x張是十元的,y張是五十元的
根據題目的意思x+y=7 且 x=y+1 或 x=y-1 ->兩種可能
但是題目最後問minimum possible value of the checks that were lost
也就是你先前花越多錢,損失越少,故選 x=y-1
(這樣五十元check比十元的多花一張)
故 x+y=y-1+y=2y-1=7 2y=8 y=4 所以 x=3
消耗金額= 3*10+4*50=230
所求=丟掉的金額=1500-230=1270
: 7. Tickets for all but 100seats in a 10000-seat stadium were sold. Of the
: tickets sold, 20 percent were sold at half price and the remaining tickets
: were sold at the full price of $2. What was the total revenue from
: tickets sales?
: (A) $15840
: (B) $17820
: (C) $18000
: (D) $19800
: (E) $21780 答案是B
由題目知道賣出9900個位子 其中 20 percent were sold at half price
故另外80 percent (remaining tickets)were sold at the full price($2)
得知票的半價為一塊
故 9900*20%*1=1980 9900*80%*2=15840 1980+15840=17820
大概是這樣吧XD
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 140.112.243.79
1F:推 whisperheart:恍然大悟!!感謝~~ 220.137.45.108 09/30 23:14