1. In a class, student either History or Geography, but not both. If the number of
students studying Geography is 50% more than those studying History, what is
the percentage of students studying History?
2. Peter sold two flats for $990,000 each. He lost 10% on one and gained 10% on
the other. After the two transactions, Peter
A. lost $20,000
B. gained $20,000
C. gainted $99,000
D had neither gain nor loss
Maths - Percentages
2013-05-23 2:39 am
回答 (3)
2013-05-23 3:26 am
✔ 最佳答案
1.(Geography:History)
150%:100%
1.5:1
3:2
60%:40%
So the percentage of students studying History is 40%
2.
peter gained: 990000*10%
peter lost:990000*10%
So the answer is D
2013-05-27 3:54 am
編號1答題者第二條答案錯誤
2013-05-26 20:14:44 補充：
第二條答案之應該是A.
2013-05-26 20:14:44 補充：
第二條答案之應該是A.
2013-05-23 8:47 am
Question 1
Let the number of student studying History be H and Geography be G
(G-H)/H = 50%
G-H=0.5H
G=1.5H
The total number of classmates = G+ H = 1.5H+H =2.5H
% of students studying History =H/2.5H =1/2.5 = 40%
Question 2
Let the price Peter bought in the two flats be x and y
According to the given information,
(990,000-x)/x = -10%=>990,000-x=-0.1x =>990,000=0.9x=>1,100,000
(990,000-y)/y = 10%=>990,000-y=0.1y=>990,000=1.1y=>y=900,000
The total cost Peter bought in the two flats are 1.1M+0.9M = 2,000,000
The total profit = 990,000*2-2,000,000 =-20,000
The answer should be "A"
Let the number of student studying History be H and Geography be G
(G-H)/H = 50%
G-H=0.5H
G=1.5H
The total number of classmates = G+ H = 1.5H+H =2.5H
% of students studying History =H/2.5H =1/2.5 = 40%
Question 2
Let the price Peter bought in the two flats be x and y
According to the given information,
(990,000-x)/x = -10%=>990,000-x=-0.1x =>990,000=0.9x=>1,100,000
(990,000-y)/y = 10%=>990,000-y=0.1y=>990,000=1.1y=>y=900,000
The total cost Peter bought in the two flats are 1.1M+0.9M = 2,000,000
The total profit = 990,000*2-2,000,000 =-20,000
The answer should be "A"
參考: ME
收錄日期: 2021-04-26 14:09:14
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20130522000051KK00291