1. The age of Sam's father is 3 years more than 4 times that of Sam now.
3 years ago, the sum of their ages was 47. How old are Sam and his father now?
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中二數學一條【求完整說明及回答】
2014-04-27 2:50 am
回答 (1)
2014-04-27 3:07 am
✔ 最佳答案
let sam's age be x and the age of his father be y,
4x+3=y..(i)
(x-3)+(y-3)=47..(ii)
from(ii):
x+y=53
y=53-x..(iii)
put(iii) into (i)
4x+3=53-x
5x=50
x=10
put x=10 into (ii)
y-3=40
y=43
sam is 10 years old and his father is 43 years old now.
收錄日期: 2021-04-28 14:23:54
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20140426000051KK00143