Kimberly77 wrote:
BrentGMATPrepNow wrote:
Bunuel wrote:
If snow falls at a rate of x centimeters per minute, how many hours would it take for y centimeters to fall?
A. \(\frac{x}{60y}\)
B. \(\frac{y}{60x}\)
C. \(\frac{60x}{y}\)
D. \(\frac{60Y}{x}\)
E. 60xy
Important: We're given information about the rate of snowfall in centimeters per MINUTE, but the question asked us to provide our answer in terms of HOURS.
So, our first step is to convert the rate to centimeters per HOUR.
If snow falls at a rate of x centimeters per MINUTE, then we can also say that the snow falls at a rate of
60x centimeters per HOUR (since there are 60 minutes in 1 hour).
How many hours would it take for y centimeters to fall?time = output/ratePlug in our values to get: time =
y/
60xAnswer: B
Hi Brent
BrentGMATPrepNow, in time conversion here, we use min of 60 in converting min to hr but in rate = output/time, we use 1 to represent 60x/1hr ? Getting a bit confused that in time conversion 1 represent 1hr here but 60 represent 60 min?
Here's one way to think about it:
If snow falls at a rate of x centimeters per minute, then:
- after 1 minute, we have x cm of snow.
- after 2 minutes, we have 2x cm of snow.
- after 3 minutes, we have 3x cm of snow.
- after 4 minutes, we have 4x cm of snow.
- after 5 minutes, we have 5x cm of snow.
.
.
.
- after 60 minutes, we have 60x cm of snow.
Note: 60 minutes = 1 hour
So we can all say: after 1 hour, we have 60x cm of snow.
This means the RATE of snowfall is 60x cm per HOUR
We can also say the RATE of snowfall is 60x cm per 1 HOUR (this has the same meaning as the sentence above)
Once we written the RATE in terms of centimeters per HOUR, we can apply the
time = output/rate formula.
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