F.4 MATHS......................
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F.4 MATHS
2010-05-29 2:04 am
回答 (2)
2010-05-29 3:13 am
✔ 最佳答案
3)z=kxy, where k is a constant
z'=k[(1-25%)x][(1+50%)y]=k(0.75x)(1.5y)=1.125kxy=1.125z
percentage increased=(1.125z-z)/z*100%=12.5%
4)
R=kl/A, where k is a constant
For wire A, R(a)=kl(a)/A(a)...(1)
For wire B, R(b)=kl(b)/A(b)...(2)
R(a)/R(b)=[l(a)/l(b)]*[A(b)/A(a)]=(3/5)(9/16)=27/80
the ratio is 27:80
2010-05-29 2:43 am
3)
(1 - 0.25)(1.5) = 1.125
+ 12.5%
4)
(3/16) : (5/9)
= 3*9 : 16*5
= 27 : 80
(1 - 0.25)(1.5) = 1.125
+ 12.5%
4)
(3/16) : (5/9)
= 3*9 : 16*5
= 27 : 80
收錄日期: 2021-04-21 22:12:43
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20100528000051KK02894