百分率 (式+步驟+答案)
1. This year Mr Chan's weekly salary is $5600.This is $600 more than last year's salary.What is the percentage increase in salary?
2. Henry added 0.8 L of white paint to 2.4 L of red paint.What percentage of the mixture was red paint?
3. Twenty per cent of a block of ice melted away.Another 25% of the remainer was sold.What percentage of the original block of ice reained?
4. In February,a worker's income increased by 20% over his January income.However , in March his income decreased by 20% over hhis February income.What percentage of his January income was his March income.
英文數學功課問題
2008-12-07 8:08 pm
回答 (2)
2008-12-07 8:24 pm
✔ 最佳答案
1. last year salary = 5600-600 = 5000percentage increased = 600/5000x100% = 12%
2. total volume = 0.8+2.4 = 3.2
percentage of the mixture of red paint
= 2.4/3.2x100%
=75%
3. Define M as the original mass of ice
remainer of ice after meld = M*(1-0.2) = 0.8M
remainer of ice after sold = (0.8M)*(1-0.25) = 0.6M
Therefore, 60% of the original block of ice retained.
4. Define S be the salary of the worker in Jan
Salary of the worker in Feb = 1.2S
Salary of the worker in March = (1.2S)*0.8 = 0.96S
Therefore, 96% of salary in Jan was in March
2008-12-07 8:40 pm
1)600/5600-600*100%
=600/5000*100%
=12%
the percentage increase in salary is 12%.
2)2.4/2.4+0.8*100%
=2.4/3.2*100%
=24/32*100%
=75%
the percentage of the mixture was 75%
3)20*(1-25%)
=20*75%
=15
4)0.96/0.8
=96%
96% of salary in Jan was in March
=600/5000*100%
=12%
the percentage increase in salary is 12%.
2)2.4/2.4+0.8*100%
=2.4/3.2*100%
=24/32*100%
=75%
the percentage of the mixture was 75%
3)20*(1-25%)
=20*75%
=15
4)0.96/0.8
=96%
96% of salary in Jan was in March
收錄日期: 2021-04-13 16:18:02
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20081207000051KK00565