A certain population of bacteria doubles every 10 minutes.If the number of bacteria in the population initially was 10^4, what was the number in the population 1 hour later?
A)2(10^4)
B)6(10^4)
C)(2^6)(10^4)
D)(10^6)(10^4)
E)(10^4)6
Thank you in advance.
Population problem
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Population after 10 minutes = 2*(10^4) = (2^1)*(10^4)shanice wrote:A certain population of bacteria doubles every 10 minutes.If the number of bacteria in the population initially was 10^4, what was the number in the population 1 hour later?
Population after 20 minutes = 2*2*(10^4) = (2^2)*(10^4)
Population after 30 minutes = 2*2*2*(10^4) = (2^2)*(10^4)
...
Population after 60 minutes = = (2^6)*(10^4)
The correct answer is C.
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Since the population doubles every 10 minutes, in 60 minutes it will be multiplied by 2 six times:shanice wrote:A certain population of bacteria doubles every 10 minutes.If the number of bacteria in the population initially was 10^4, what was the number in the population 1 hour later?
A)2(10^4)
B)6(10^4)
C)(2^6)(10^4)
D)(10^6)(10^4)
E)(10^4)6
Thank you in advance.
10â�´ * (2*2*2*2*2*2) = 2â�¶10â�´.
The correct answer is C.
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To [email protected] & GMATGuruNY,
I understand your workings and the explanation for this problem but I have a doubt. When I read the question, the following sentence lead me to this understanding:
"A certain population of bacteria doubles every 10 minutes".
So, I understood it as below:
Time Population
Now 10^4
10 10^4 + 10^4 (Isn't doubling supposed to be this way?)
20
However, I couldn't solve the question because I got stuck with the computation. What's wrong with my understanding here?
I'm sorry for asking such a silly question but I really need to know.
Thank you, guys.
I understand your workings and the explanation for this problem but I have a doubt. When I read the question, the following sentence lead me to this understanding:
"A certain population of bacteria doubles every 10 minutes".
So, I understood it as below:
Time Population
Now 10^4
10 10^4 + 10^4 (Isn't doubling supposed to be this way?)
20
However, I couldn't solve the question because I got stuck with the computation. What's wrong with my understanding here?
I'm sorry for asking such a silly question but I really need to know.
Thank you, guys.
 anuprajan5
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Shanice,
I think your confusion stems from the difference between double and multiply. If it was multiplying, then your logic works. Doubling is double a certain number.
Example  double 4  4*2
multiply 4  4*4
Regards
Anup
I think your confusion stems from the difference between double and multiply. If it was multiplying, then your logic works. Doubling is double a certain number.
Example  double 4  4*2
multiply 4  4*4
Regards
Anup