power prep

dunkin77 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?

a) 5x/18
b) 6x/5
c) 18x/5
d) 60x
e) 3,600,000x

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:

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

18x/5 = y

Answer: C