During a spring season, a certain glacier surged at . . . .

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During a spring season, a certain glacier surged at the rate of 1 mile per 100 days. What was its rate in feet per hour? (1 mile = 5,280 feet)

A. 5/11
B. 11/5
C. 55
D. 110
E. 22,000

The OA is the option B.

How can I find the rate? What is the formula I should use to make the transformation? Experts, can you give me some help. Thanks.

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by EconomistGMATTutor » Tue Jan 16, 2018 10:26 am
Hello Vincen.

Let's take a look at your question.

glacier surged at the rate of 1 mile per 100 days, it implies that his rate is $$\frac{1}{100}\ \frac{miles}{days}.$$ Now, we have to convert from miles to feet and from days to hours.

Now, 1 mile = 5,280 feet and 1 day = 24 hours. Hence, the rate is $$\frac{1}{100}\ \frac{miles}{days}\cdot\frac{5,280}{1}\ \frac{feet}{miles}\ \cdot\ \frac{1}{24}\ \frac{day}{hours}=\frac{11}{5}\frac{feet}{hours}.$$ This is why the correct option is B.

I hope this answer can help you.

Feel free to ask me again if you have a doubt.

Regards.
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by [email protected] » Wed Jan 17, 2018 11:10 am
Hi Vincen,

We're told that a certain glacier surged at the rate of 1 mile in 100 days. We're asked for its rate in feet per hour? (1 mile = 5,280 feet). Based on how the answer choices are 'spaced out', you can answer this question with just a little math and some estimation.

To start, there are 24 hours in 1 day, so there are (24)(100) = 2400 hours of travel in 100 days.

Since the iceberg traveled 1 mile, its rate was:

5280 feet/2400 hours

4800 is twice 2400, so this iceberg traveled a little more than 2 feet per day. There's only one answer that's a little more than 2....

Final Answer: B

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by Jeff@TargetTestPrep » Mon Feb 26, 2018 10:39 am
Vincen wrote:During a spring season, a certain glacier surged at the rate of 1 mile per 100 days. What was its rate in feet per hour? (1 mile = 5,280 feet)

A. 5/11
B. 11/5
C. 55
D. 110
E. 22,000
Since 1 mile = 5280 feet and since 100 days is 100 x 24 = 2400 hours, the rate in feet per hour is:

5280/2400 = 528/240 = 66/30 = 11/5

Answer: B

Jeffrey Miller
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