...17:16:50 補充： But I would present it this way: Suppose he bought X apples. (OR Let X be the no. of apples...
Logic, Logic, and Logic George Boolos 這是一本好專業的數理邏輯書籍。我覺得隨便走進一間書局一定不會在書架上見到。最好的方法是去學術專業圖書中心訂購。你可以試試網上查詢先 http://www.apbookshop.com/top_bar/enquiry/enquiry.asp 若果他們有...
buy ruler x pen y x+y=39.....1 5x+6y=200.....2 2-1*5 5x+6y-(5x+5y)=200-39*5 y=5 x=34 so Ann buys 5 pens 應該是這樣
(1) 大眾書店 ( Popular ) 地址：新界沙田新城市廣場第一期 4 樓 445 - 447 號 地址：將軍澳君薈坊 1 樓 F01 號 大眾書店各款計算機售價（港元）( 15 FEB 2007 ) Casio FX-50F $179 Sharp EL-506V $125 Casio...
(c) Methods of buying 2 books using ≦ $50 are: {16+16,16+20,16+28,16+34, 20+20... buying 1 book using ≦ $50 are: {16, 20, 28, 34} ∴ no. of ways buying 1 book using ≦ $5 = 6*8*4*6 = 1,152 Method of buying 3...
Donna buys some $2stamps and some $5 stamps .If she spends $54 altogether and...
Let $y be the price of each stamp after the price increase. Then the price of each stamp before the price increase = $(y - 0.3) Cost of 60 stamps before the price increase = $60(y - 0.3) Cost of (60 - 12) stamps after the price increase = $(60 - 12)y 60(y - 0.3) = (60 - 12)y 60y - 18 = 48y 12y = 18 y...
I spend $68 in buying apples at 5 for $3 and oranges at 5 for $2. I sell three... a be the number of apples bought . then a*3/5 is the money spent on apples. money spent on oranges...
