If in a certain population, people are born at an average rate of 9...

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If in a certain population, people are born at an average rate of 9 people every 2 seconds and people die at an average rate of 3 people every 2 seconds, by approximately how many people does the population increase in 1 day?

A. 17,280
B. 25,920
C. 129,600
D. 259,200
E. 388,800

OA D
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AAPL wrote:
Wed Jan 22, 2020 7:20 am
GMAT Prep

If in a certain population, people are born at an average rate of 9 people every 2 seconds and people die at an average rate of 3 people every 2 seconds, by approximately how many people does the population increase in 1 day?

A. 17,280
B. 25,920
C. 129,600
D. 259,200
E. 388,800

OA D
Given that people are born at an average rate of 9 people every 2 seconds and people die at an average rate of 3 people every 2 seconds, the population grows at a rate of 9 – 3 = 6 people per 2 seconds or 3 people per second.

Thus, in 1 day, the population would grow 3*24*60*60 = 259,200.

The correct answer: D

Hope this helps!

-Jay
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AAPL wrote:
Wed Jan 22, 2020 7:20 am
GMAT Prep

If in a certain population, people are born at an average rate of 9 people every 2 seconds and people die at an average rate of 3 people every 2 seconds, by approximately how many people does the population increase in 1 day?

A. 17,280
B. 25,920
C. 129,600
D. 259,200
E. 388,800

OA D
The growth rate, i.e., the difference between the number of people born and those who have died, per second, is:

9/2 - 3/2 = 4.5 - 1.5 = 3

So the growth rate is 3 x 3600 x 24 = 259,200 per day.

Answer: D

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