Population problem

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.

Since the population doubles every 10 minutes, in 60 minutes it will be multiplied by 2 six times:
10� * (2*2*2*2*2*2) = 2�10�.

The correct answer is C.

C is the correct answer.

Thank you, guys.

To Anurag@Gurome & 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.

Can someone please reply me on this?

Thank you.

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