2. If a-b=10 and ab=k,express a^2b^2 in terms of k.
3.If a:b=3:4 and a:c=2:5, find
(A)a:b:c
(B)The value of ac/a^2+b^2
7(C) If he sells the amount in 10120 at the rate of 1(British pounds)=HK$14.5,
how much does he get in HK dollars?
MATHS中一
2010-05-19 3:47 am
回答 (1)
2010-05-19 3:57 am
✔ 最佳答案
2. a^2b^2 = (ab)^2 = k^23.a. a : b = 3 : 4, a : c = 2 : 5
From a : b, we get a/b = 3/4, b = 4a/3
From a : c, a/c = 2/5, c = 5a/2
So, a : b : c
= a : (4a/3) : (5a/2)
= 1 : 4/3 : 5/2
= 6 : 8 : 15
b. ac/(a^2 + b^2)
= a(5a/2)/[a^2 + (4a/3)^2]
= (5a^2/2)/(25a^2/9)
= (5/2)/(25/9)
= 9/10
7. He gets:
= 10 120 pounds X 14.5 HK$ / 1 pound
= 10 120 X 14.5
= HK$ 146 740
參考: Prof. Physics
收錄日期: 2021-04-19 22:15:18
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20100518000051KK01245