Re: [計量] 好多題計量問題
y※ 引述《peilinchen (peilin)》之銘言：
: 圖表題(真糟糕我的圖表題一直是我的痛)
: 1. Family X's gross income is the sum of Mr. X's income and Mrs. X's income.
: In 1983 Mr. and Mrs. X each had an income of $25,000. If Mr. X's income
: increased by 10 percent from 1983 to 1984, by what percent did Mrs. X's
: income decrease for the same period?
: (A) 10%
: (B) 15%
: (C) 20%
: (D) 25%
: (E) 30%
: Ans: E
25000*1.1 +25000*(1-x)=45000
x=0.3
: 2. By approximately what percent did the amount that Family X put into
: savings decrease from 1983 to 1984?
: (A) 13%
: (B) 23%
: (C) 35%
: (D) 45%
: (E) 57%
: Ans: E
1983: 50000*0.25=12500 1984: 45000*0.12=5400
5400-12500/12500=-0.568
: If $4,500 was invested in a bond fund when the proce per share was
: $9 and #3,000 was invested in the fund when the price per share was
: $10, what was the average (arithmetic mean) price per share purchased?
: (A) $9.625
: (B) $9.50
: (C) $9.40
: (D) $9.375
: (E) $9.20
: Ans: D (不懂題目的意思)
5743
: n > 0
: Column A Column B
: n(n+1)+n+1/(n+1)^2 1
: Ans: C
n*(n+1)+n+1=n^2+2*n+1=(n+1)^2
: A rectangular rug covers half of a rectangular floor that is 9 feet wide
: and 12 feet long. If the dimensions of the rug are in the same ration
: as those of the floor, how many feet long is the rug?
: (A) 6
: (B) 21/2
: (C) 2√7
: (D) 6√2
: (E) 4√6
: Ans: D
9*12*x^2=54
x=1/√2
12*1/√2=6√2
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 118.160.23.176
推
10/05 11:28, , 1F
10/05 11:28, 1F
→
10/05 11:29, , 2F
10/05 11:29, 2F
→
10/05 12:04, , 3F
10/05 12:04, 3F
討論串 (同標題文章)