1.$5400 is divided among three person :A ,B, C.A gets twice the amount of B,while C gets $600 more than 3 times B’s amount . how much does each of them got?
2.Victor’s running speed is twice his walking speed. After running for2 hours and then walking for 3 hours,he has traveled 21 km. What is his walking speed?
Please use one unknown
form 1 maths
2008-02-18 12:26 am
回答 (2)
2008-02-18 12:34 am
✔ 最佳答案
Let A=2BC=600+3B
i.e 5400= 2B+B+600+3B
B=800
A=2(800)=1600
C=600+3(800)=3000
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Let walking speed be X
i.e running speed=2X
2X(2)+3X=21
X=3 km/h
參考: myself
2008-02-18 12:36 am
1. A=2B-(1), C+600=3B-(2), A+B+C=5400-(3)
From (2), C=3B-600 & A=2B
Put A & C into (3)
2B+B+3B-600=5400
6B=6000
B=1000
A=2000
C=4000
2. Let victor's walking speed is Y km/h, his running speed is 2Y km/h.
2Yx2 + Yx3 = 21km
7Y=21km
Y=3km/h
His walking speed is 3km/h
From (2), C=3B-600 & A=2B
Put A & C into (3)
2B+B+3B-600=5400
6B=6000
B=1000
A=2000
C=4000
2. Let victor's walking speed is Y km/h, his running speed is 2Y km/h.
2Yx2 + Yx3 = 21km
7Y=21km
Y=3km/h
His walking speed is 3km/h
參考: 我
收錄日期: 2021-04-14 19:57:44
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https://hk.answers.yahoo.com/question/index?qid=20080217000051KK02697