If the speed of x meters per second is equivalent to the speed of y kilometers per hour, what is y in terms of x?
[spoiler]OA 18x/5[/spoiler]
looks too simple but i got totally confused!
x meters per second is y kilometers per hour...
This topic has expert replies
x/1000/ 1/3600Nailya wrote:If the speed of x meters per second is equivalent to the speed of y kilometers per hour, what is y in terms of x?
[spoiler]OA 18x/5[/spoiler]
looks too simple but i got totally confused!
18x/5

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Hi lav,lav wrote:y is speed in km/sec
x is same speed in m/sec
hence if we convert y to m/sec it must be equal to x
1000 * y / 3600 = x
solve it you get
y= 18*x/5
I think you meant y km/hr not sec.
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Picking numbers is a great way to answer questions that are confusing.Nailya wrote:If the speed of x meters per second is equivalent to the speed of y kilometers per hour, what is y in terms of x?
We want y in terms of x, so let's pick a number for x. To keep things simple, let's let x = 1m/s.
To convert metres to kilometres, we divide by 1000.
To convert seconds to hours, we divide by 3600.
So, 1m/s = (1/1000)km/(1/3600)h = 3600/1000(km/h) = 36/10(km/h) = 18/5(km/h)
Since we picked x = 1, we look for the answer that works out to 18/5 when we plug in x=1, which based on your spoiler is (18/5)x.
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There are 3,600 seconds in an hour and 1,000 meters in a kilometer. So, let's convert y kilometers/hour to meters/second:Nailya wrote:If the speed of x meters per second is equivalent to the speed of y kilometers per hour, what is y in terms of x?
We can start by converting y kilometers to meters.
y kilometers = 1,000y meters
Next we can convert 1 hour to seconds.
1 hour = 3,600 seconds
Thus, y km/hr can be expressed as 1,000y/3,600 m/sec, or 5y/18 m/sec after it's simplified.
Since our two rates are equal, x = 5y/18. We need to solve this equation for y.
18x = 5y
[spoiler]18x/5 = y[/spoiler]
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