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Bunuel
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ankushbassi
Bunuel,
Do you really think such easy questions appears in the exam?
I believe GMAT posts very simple weekly questions.

Yes, this question is very easy but one can still encounter 1 or 2 such easy questions on the test.
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Answer = 4 * 20 = 80

Answer = A
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1 min = 15*4 sec
for 20 minutes, its 4*20 = 80. Answer is A
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I basically used the RTW chart and converted 15 sec to 0.25 minutes. I then divided 20 by 0.25, resulting in 80.
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This is actually a GMAT question. :)
4 clones every minute. 20 minutes -> 80 new clones :)
the empire will strike back :D
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This is actually a GMAT question. :)
4 clones every minute. 20 minutes -> 80 new clones :)
the empire will strike back :D

A possibility as all the questions in Official Guides/GMATPREP free or exam pack 1 or question pack 1 are officially retired questions from actual GMAT exams.
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Increase of 1 person per 15 seconds is equivalent to a increase of 4 person/minute
So in 20 minutes increase = 20 * 4 = 80 persons
correct answer - A
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Bunuel

GMAT weekly questions


If the population of a certain country increases at the rate of one person every 15 seconds, by how many persons does the population increase in 20 minutes?

A. 80
B. 100
C. 150
D. 240
E. 300


try not to make it complicated
15s= 1


20*60=1200s

15 =>1

1200 => ?

1200*1 / 15 =80
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Quote:

If the population of a certain country increases at the rate of one person every 15 seconds, by how many persons does the population increase in 20 minutes?

A. 80
B. 100
C. 150
D. 240
E. 300

We are given that a population increases by 1 person every 15 seconds and we need to determine how many people it will increase by in 20 minutes, which is 20 x 60 = 1200 seconds. We can let x = the number of people increased in 20 minutes and create the following proportion:

1/15 = x/1200

15x = 1200

x = 80

Alternate Solution:

One person every 15 seconds equals 4 people per minute. Thus, in 20 minutes, we have 4 x 20 = 80 people.

Answer: A
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Solution



Given
• The population of a certain country increases at the rate of one person every 15 seconds
To find
• How many persons does the population increase in 20 minutes?
Approach and Working out
• Population increased in 15 sec= 1
• Population increased in 60 sec or 1 min= 1*4 = 4
o Population increased in 20 min= 4*20 = 80

Thus, option A is the correct answer.

Correct Answer: Option A
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Total seconds in 20 minutes = 20*60 = 1200

Since the rate of increase is 1 person per 15 seconds,

In 1200 seconds, the total increase will be 1200/15 = 80

Thus, the correct answer is A.
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