一條英文數學題,請大家幫幫忙！
Eric is five years younger than his sister. Five years ago, his age 1/6 of his sister.how old is Eric now？
一條英文數學題,請大家幫幫忙！
2006-12-24 5:00 am
回答 (5)
2006-12-24 5:12 am
✔ 最佳答案
Let E be the age of Eric and S be the age of his sisterE + 5 = S
S = E + 5 -----------------------(1)
6(E - 5) = S - 5
6E - 30 = S - 5
6E - S = 25----------------------(2)
sub (1) into (2),we have
6E - (E + 5) = 25
5E - 5 = 25
5E = 30
E = 6
∴Eric is 6 years old.
2006-12-24 5:19 am
Let A be the age of Eric now & B be the age of his sister now
A + 5 = B --- (1)
(B - 5) x 1/6 = A - 5 --- (2)
Put (1) into (2)
(A + 5 - 5) x 1/6 = A - 5
A / 6 = A - 5
A = 6A - 30
5A = 30
A = 6
Put A = 6 into (1)
6 + 5 = B
B = 11
Hence, Eric is 6 years old.
A + 5 = B --- (1)
(B - 5) x 1/6 = A - 5 --- (2)
Put (1) into (2)
(A + 5 - 5) x 1/6 = A - 5
A / 6 = A - 5
A = 6A - 30
5A = 30
A = 6
Put A = 6 into (1)
6 + 5 = B
B = 11
Hence, Eric is 6 years old.
2006-12-24 5:14 am
6 years old
Let Eric be x years old now.
x-5=(x+5-5)(1/6)
x-5=x/6
x-x/6=5
5/6x=5
x=6
Therfore Eric is 6 years old now
Let Eric be x years old now.
x-5=(x+5-5)(1/6)
x-5=x/6
x-x/6=5
5/6x=5
x=6
Therfore Eric is 6 years old now
2006-12-24 5:13 am
我的gramma好廢，唔好笑我
LetYbe Eric's age,
Y+5 be his sister's age
Y-5+(Y+5)-5=1/6ｙ+ｙ
2Y-5 = 7/6Y
2Y = 7/6Y+5
2Y-7/6Y = 5
5/6Y = 5
Y = 6
so Eric is 6 years old now.
2006-12-23 21:15:27 補充：
用一元一次方就可以計到啦(。^ v ^。)
LetYbe Eric's age,
Y+5 be his sister's age
Y-5+(Y+5)-5=1/6ｙ+ｙ
2Y-5 = 7/6Y
2Y = 7/6Y+5
2Y-7/6Y = 5
5/6Y = 5
Y = 6
so Eric is 6 years old now.
2006-12-23 21:15:27 補充：
用一元一次方就可以計到啦(。^ v ^。)
參考: 自己
收錄日期: 2021-04-23 13:17:39
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20061223000051KK03904