A is 40% older than B, and B is 20% older than C.
a). By how much percent is A older than C?
b). By how much percent is C younger than A.
percentage question---urgent
2007-10-12 4:16 am
回答 (2)
2007-10-12 4:38 am
✔ 最佳答案
a. 68%b.40.5%
2007-10-12 5:17 am
Let the age of C be c years old
Let the age of B be b years old
Let the age of A be a years old
Thus, b = 1 * 120% c = 1.2c
Thus, a = 1 * 140%b = 1.4b = 1.4 * 1.2c = 1.68c
a) Percent A is older than C =
(a - c) * 100% / c =
(1.68c - c) * 100% / c =
68% (Ans.)
b) Percent C is younger than A =
(c - a) * 100% / a =
(c - 1.68c) * 100% / 1.68c =
(-0.68c) * 100% / 1.68c =
40.48% younger (ans.)
希望幫到你.
Let the age of B be b years old
Let the age of A be a years old
Thus, b = 1 * 120% c = 1.2c
Thus, a = 1 * 140%b = 1.4b = 1.4 * 1.2c = 1.68c
a) Percent A is older than C =
(a - c) * 100% / c =
(1.68c - c) * 100% / c =
68% (Ans.)
b) Percent C is younger than A =
(c - a) * 100% / a =
(c - 1.68c) * 100% / 1.68c =
(-0.68c) * 100% / 1.68c =
40.48% younger (ans.)
希望幫到你.
收錄日期: 2021-04-13 13:51:51
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20071011000051KK03291