1.)Victor's running speed is twice his walking speed.After running for 2 hours and then walking for 3 hours ,hehas travelled 21km.What is his walking speed?
What is the meaning??
and give me a equation??
Maths question:
2006-11-08 2:15 am
回答 (5)
2006-11-08 2:23 am
✔ 最佳答案
Victor 跑步速度是他步行速步的兩倍。當佢跑了 2 小時之後步行了 3 小時後，佢經過了 21 公里。請問他的步行速度是多少？Let his walking speed = x km/hr
then his running speed = 2x km/hr
2(2x) + 3(x) = 21
4x + 3x = 21
x = 3
Therefore his walking speed is 3 km/hr.
2006-11-10 5:58 am
the best one..
2006-11-08 2:24 am
Let a be the walking speed
3 hours walking + 2 hours running = 21 km
3 x a + 2 x (2 x a) = 21 km
3a + 4a = 21km
7a = 21 km
Victor's walking speed = 21/7 km = 3 km per hour
3 hours walking + 2 hours running = 21 km
3 x a + 2 x (2 x a) = 21 km
3a + 4a = 21km
7a = 21 km
Victor's walking speed = 21/7 km = 3 km per hour
2006-11-08 2:22 am
X係行o既speed
咁run就係2x
run左2個鐘即係2乖2x=4x
行左3個鐘即係3乖x=3x
搞左咁3個鐘之後,,,,travelled左21km..
即係4x+3x=21km
7x=21km
x=3km
強烈建議下次問問題記得講唔該..
同問之前先查查字典
咁run就係2x
run左2個鐘即係2乖2x=4x
行左3個鐘即係3乖x=3x
搞左咁3個鐘之後,,,,travelled左21km..
即係4x+3x=21km
7x=21km
x=3km
強烈建議下次問問題記得講唔該..
同問之前先查查字典
2006-11-08 2:20 am
Let his walking speed be y km/h,then his running speed is 2y km/h.
2(2y)+3y=21
4y+3y=21
7y=21
y=3
Therefore his walking speed is 3km/h.
2(2y)+3y=21
4y+3y=21
7y=21
y=3
Therefore his walking speed is 3km/h.
收錄日期: 2021-04-13 13:47:57
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