Bugle Bay population

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Bugle Bay population

by kanha81 » Sat May 30, 2009 10:49 am
Over the last 10 years ago the turtle population of Bugle Bay has increased 250%. If 10 years ago, there were 50,000 turtles, and 2 years ago there were 100,000 turtles, by what percent did the Bugle Bay turtle population increase over the last 2 years?

A) 75%
B) 66%
C) 50%
D) 33%
E) 25%
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by truplayer256 » Sat May 30, 2009 11:08 am
If the population of the turtles at Bugle Bay ten years ago was 50,000, then the population of the turtles at Bugle Bay to this very day would be 50,000*3.5 or 175,000. We are told that 2 years ago, the population of the turtles at Bugle Bay was 100,000. In order to find the percent increase of the population of turtles at Bugle Bay over the last 2 years, we do the following:

(175,000-100,000)/100,000*100=75% A.

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by kanha81 » Sat May 30, 2009 11:32 am
truplayer256 wrote:If the population of the turtles at Bugle Bay ten years ago was 50,000, then the population of the turtles at Bugle Bay to this very day would be 50,000*3.5 or 175,000. We are told that 2 years ago, the population of the turtles at Bugle Bay was 100,000. In order to find the percent increase of the population of turtles at Bugle Bay over the last 2 years, we do the following:

(175,000-100,000)/100,000*100=75% A.
Nope. That's not right! I came to the same conclusion in my first attempt.
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by truplayer256 » Sat May 30, 2009 11:46 am
I don't know any other way to approach the question then. Are you sure there isn't a mistake in the OA?

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Re: Bugle Bay population

by exhilaration » Sat May 30, 2009 12:34 pm
kanha81 wrote:Over the last 10 years ago the turtle population of Bugle Bay has increased 250%. If 10 years ago, there were 50,000 turtles, and 2 years ago there were 100,000 turtles, by what percent did the Bugle Bay turtle population increase over the last 2 years?

A) 75%
B) 66%
C) 50%
D) 33%
E) 25%
250% of 50,000 = 125,000 Now
125,000-100,000 (2 years ago) = 25,000 / 100,000 = 25% (E)

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by truplayer256 » Sat May 30, 2009 12:41 pm
250% of 50,000 = 125,000 Now
125,000-100,000 (2 years ago) = 25,000 / 100,000 = 25% (E)
The questions says a 250% increase.

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by exhilaration » Sat May 30, 2009 12:49 pm
truplayer256 wrote:
250% of 50,000 = 125,000 Now
125,000-100,000 (2 years ago) = 25,000 / 100,000 = 25% (E)
The questions says a 250% increase.
OOPS then the answer is A. The OA must be wrong.

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by kanha81 » Sat May 30, 2009 12:54 pm
truplayer256 wrote:I don't know any other way to approach the question then. Are you sure there isn't a mistake in the OA?
Yupe. The OA is not what you think it is. I will post the answer soon..Waiting for others to respond
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by blackarrow » Sat May 30, 2009 1:02 pm
I am also getting A

75%

Unless their is some wierd trick involved, The question appears pretty straightforward!
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by kanha81 » Sat May 30, 2009 7:32 pm
blackarrow wrote:I am also getting A

75%

Unless their is some wierd trick involved, The question appears pretty straightforward!
Here's the OE solution.
Let N0: original size of pop.
N2: size of population 2 years ago
N10: size of population 10 years ago

Given:
N0 / N10 = 250/100 = 2.5
N10 = 50,000
N2 = 100,000

N0 = 2.5 * N10 = 2.5 * 50,000 = 125, 000

N0 / N2 = 125,000/100,000 = 1.25

Therefore, increase in population is 25%
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by ssmiles08 » Sun May 31, 2009 5:42 am
I guess what they mean when they say Bugle Bay has increased 250% is the total increase and not increased by 250%


I hate tricky wordings like these :!:

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by Stuart@KaplanGMAT » Sun May 31, 2009 8:03 am
ssmiles08 wrote:I guess what they mean when they say Bugle Bay has increased 250% is the total increase and not increased by 250%


I hate tricky wordings like these :!:
"Increased 250%" definitely means "increased by 250%". The explanation and official answer are just wrong.

To illustrate, let's change 250% to 50%, so our question now reads:
Over the last 10 years ago the turtle population of Bugle Bay has increased 50%.
If we accept the "official" explanation for this question, then an "increase" of 50% would actually mean a decrease to 50% - that certainly doesn't make sense.

In order for the explanation to be correct, the question would have to read:
Over the last 10 years ago the turtle population of Bugle Bay has increased to 250% of what it was 10 years ago.
What's the source? Please post the source for all of your questions, so we know if the question is reliable - a lot of questions available for free are worth exactly what you paid for them - nothing.
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by Vemuri » Sun May 31, 2009 8:06 am
What is the source of this question?

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by kanha81 » Tue Jun 02, 2009 2:33 pm
Stuart Kovinsky wrote:
ssmiles08 wrote:I guess what they mean when they say Bugle Bay has increased 250% is the total increase and not increased by 250%


I hate tricky wordings like these :!:
"Increased 250%" definitely means "increased by 250%". The explanation and official answer are just wrong.

To illustrate, let's change 250% to 50%, so our question now reads:
Over the last 10 years ago the turtle population of Bugle Bay has increased 50%.
If we accept the "official" explanation for this question, then an "increase" of 50% would actually mean a decrease to 50% - that certainly doesn't make sense.

In order for the explanation to be correct, the question would have to read:
Over the last 10 years ago the turtle population of Bugle Bay has increased to 250% of what it was 10 years ago.
What's the source? Please post the source for all of your questions, so we know if the question is reliable - a lot of questions available for free are worth exactly what you paid for them - nothing.
Stuart,
This question is from an online website (freebie) that hosts questions on GMAT and allows to practice questions under timed conditions.
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by cata1yst » Tue Jun 02, 2009 6:36 pm
kanha81 wrote:
blackarrow wrote:I am also getting A

75%

Unless their is some wierd trick involved, The question appears pretty straightforward!
Here's the OE solution.
Let N0: original size of pop.
N2: size of population 2 years ago
N10: size of population 10 years ago

Given:
N0 / N10 = 250/100 = 2.5
N10 = 50,000
N2 = 100,000

N0 = 2.5 * N10 = 2.5 * 50,000 = 125, 000

N0 / N2 = 125,000/100,000 = 1.25

Therefore, increase in population is 25%

Wrong...it is 75%.

Stupid question.