If the population of a certain country increases at the rate of one

Question

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

Bunuel · Answer

Since the population increases at the rate of 1 person every 15 seconds, it increases by 4 people every 60 seconds, that is, by 4 people every minute. Thus, in 20 minutes the population increases by 20 x 4 = 80 people.

Answer. A.

ankushbassi · Answer

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

Bunuel · Answer

Yes, this question is very easy but one can still encounter 1 or 2 such easy questions on the test.

PareshGmat · Answer

Answer = 4 * 20 = 80

Answer = A

felixthecat · Answer

1 min = 15*4 sec
for 20 minutes, its 4*20 = 80. Answer is A

pacifist85 · Answer

I basically used the RTW chart and converted 15 sec to 0.25 minutes. I then divided 20 by 0.25, resulting in 80.

mvictor · Answer

This is actually a GMAT question.

4 clones every minute. 20 minutes -> 80 new clones

the empire will strike back :D

ENGRTOMBA2018 · Answer

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.

rhine29388 · Answer

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

kamranko · Answer

try not to make it complicated 
15s= 1

20*60=1200s

15 =>1

1200 => ?

1200*1 / 15 =80

ScottTargetTestPrep · Answer

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

EgmatQuantExpert · Answer

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

GmatPoint · Answer

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.

bumpbot · Answer

Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.

If the population of a certain country increases at the rate of one

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards

GMAT Problem Solving (PS) Questions

If the population of a certain country increases at the rate of one

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards