*用方程解答*
*要步驟*
The total age of Mr.Chu and his son is 51. Three years ago, he was 8 times as old as his son. How old is his son now?
一條數學問題(中一程度)
2007-06-02 6:24 pm
回答 (6)
2007-06-02 6:27 pm
✔ 最佳答案
Let x be the age of Mr.chu.x-3=8(51-x-3)
x-3=408-8x-24
9x =387
x=43
His son is 51-43=8 years old now.
2007-06-03 4:17 pm
Set up his son's age is n years old,Mr.Chu is x years old.
n+x=51
8(n-3)=x-3
8n-24+3=x
8n-21=x
n+8n-21=51
9n=51+21
n=72 over 9
n=8
His son is 8 years old now.
n+x=51
8(n-3)=x-3
8n-24+3=x
8n-21=x
n+8n-21=51
9n=51+21
n=72 over 9
n=8
His son is 8 years old now.
2007-06-02 6:49 pm
x-3=8(51-x-3)
x-3=408-8x-24
9x =387
x=43
His son is 8 yaears old
x-3=408-8x-24
9x =387
x=43
His son is 8 yaears old
2007-06-02 6:38 pm
中文解釋：
曹先生與他的兒子總歲數是５１歲．３年之後，曹先生比他的兒子大８歲．他的兒子現在多少歲？？？
設他的兒子現在ｐ歲。
３年之後姐係曹生同兒子總歲數是５７ 曹生比佢大８歲 姐係曹生３２．５ 兒子就２４．５歲
曹先生與他的兒子總歲數是５１歲．３年之後，曹先生比他的兒子大８歲．他的兒子現在多少歲？？？
設他的兒子現在ｐ歲。
３年之後姐係曹生同兒子總歲數是５７ 曹生比佢大８歲 姐係曹生３２．５ 兒子就２４．５歲
2007-06-02 6:30 pm
Let X = Mr Chu's age now, and Y = his son's age now.
X + Y = 51
X - 3 = 8 * (Y - 3)
X - 3 = 8Y - 24
X = 8Y -24 + 3
X = 8Y - 21
8Y - 21 + Y = 51
9Y = 72
Y = 8
X = 43
X + Y = 51
X - 3 = 8 * (Y - 3)
X - 3 = 8Y - 24
X = 8Y -24 + 3
X = 8Y - 21
8Y - 21 + Y = 51
9Y = 72
Y = 8
X = 43
參考: my knowledge
2007-06-02 6:28 pm
Let the age of Mr. Chu's son is x, the age of Mr. Chu is 51-x
8(x-3)=51-x-3
8x-24=48-x
9x=72
x=8
The age of his son is 8 now
8(x-3)=51-x-3
8x-24=48-x
9x=72
x=8
The age of his son is 8 now
收錄日期: 2021-04-13 00:34:09
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20070602000051KK00990