If the speed of x metres per second is equivalent to the speed of y kilometres per hour , what is y in terms of x?
(1 kilometers = 1000 metres).
A) 5x/18
B) 6x/5
C) 18x/5
D) 60x
E) 3600,000x.
C
Gmat prep 1 Ques
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hope this might clear it up:
the speed of y is km/hour and you know that 1km=1,000m. you also know that 1 hour is equal to 3600 seconds.
km> x/1000
hr> 3600
so y= [x/1000]/3600 > multiply x/1000 by 3600/1 > 3600x/1000 and simplify for 18x/5
the speed of y is km/hour and you know that 1km=1,000m. you also know that 1 hour is equal to 3600 seconds.
km> x/1000
hr> 3600
so y= [x/1000]/3600 > multiply x/1000 by 3600/1 > 3600x/1000 and simplify for 18x/5
"x meters per second is equivalent to the speed of y kilometers per hour"means x/1"second" = y/1 "hour" (*)
We know that 1kilometer = 1000 meters and that 1 hour = 3600 seconds
Therefore, (*) can be written as x/1000 * 1"second" = y/3600 seconds
=> y=3600x/1000 = 18x/5
You can take a real number and try to convert it in to m/s or km/h, then you will figure out
We know that 1kilometer = 1000 meters and that 1 hour = 3600 seconds
Therefore, (*) can be written as x/1000 * 1"second" = y/3600 seconds
=> y=3600x/1000 = 18x/5
You can take a real number and try to convert it in to m/s or km/h, then you will figure out

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