陈向东 真题150(142/146) 两道复杂应用题

fierceli

Paint B takes one-third longer to apply than paint A.

我觉的这两个概念是一致的，显然是假设了刷同样面积的前提下

kitebird

第二题的答案是D？？？？

fierceli

呵呵 是啊 我也很郁闷

期待N人指点江山啊

raikey

1 A home owner must pick between paint A, which costs 6 dollar per liter, and paint B, which costs 4.5 dollar per liter. Paint B takes one-third longer to apply than paint A. If the home owner must pay the cost of labor at the rate of 36 dollar per hour, which of the two paints will be cheaper to apply?

(1) the ratio of the area covered by one liter of paint A to the area covered by paint B is 4:3

(2) Paint A will require 40 liters of paint and 100 hours of labor

题目说: A是$6/L  B是$4.5/L

此外我对"Paint B takes one-third longer to apply than paint A"的理解是:"如果使用A共花了n小时,那么使用B总共要花4n/3小时"

(1)=> 如果使用A来刷需要x升,那么换用B来刷就要4x/3升 => A的开销=6x+36n,B的开销=4.5x+36n*4/3无法比较

(2)=> A的开销=6*40+36*100 ,但B要用多少升不知道,故也不能比较

(1)&(2) => A的开销=6*40+36*100, B的开销=4.5*40*4/3 + 36*100*4/3 可以比较

所以这题我选C

raikey

2 In a certain law firm there are five senior partners and five junior partners and all senior partners receive bonuses greater than those of the junior partner. Does senior partner J receive the largest bonus of the lawyers at the firm?

(1) J receives a bonus greater than twice the average bonus for all the senior partners

(2) All partners receive some bonus, and Mr. J receives five times the average given to all the partners

这题我这么考虑:设5个Senior的总奖金数是S1,5个Junior的总奖金数是S2.

(1)=> J的所得>2*S1/5即(0.4S1,S1)之间,除去他剩下的4人总数在(0,0.6S1)之间,有可能有人拿得比J多.

      例如:J=0.41S1,另一人拿0.42S1,剩余3人共拿0.17S1.

(2)=> J>5*(S1+S2)/10即0.5(S1+S2),注意总数是S1+S2,所以剩余的9人最多在S1+S2-0.5(S1+S2)里分,

也就是在0.5(S1+S2)里分,所以不可能有其他人拿得比J多.

故该题选B

fierceli

(1)=> 如果使用A来刷需要x升,那么换用B来刷就要4x/3升 => A的开销=6x+36n,B的开销=4.5x+36n*4/3无法比较

题目说: A是$6/L  B是$4.5/L

楼上的错了

A的开销为6x+36n B的开销为4x/3 *4.5+48n=6x+48n

fierceli

N人给讲讲第二题啊！

szy733

up

szy733

up

CHENCHENKYLE

第一题关键在于第一个选项的理解，指的是1liter的A和B的比率，但是B是几liter不得而知，所以无从下手
                      第二个选项只知道A的不知道B的也是无从下手