bacteria population

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Source: — Data Sufficiency |

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by ajith » Sat Feb 20, 2010 3:09 am
gmatnmein2010 wrote:By what percent will the bacteria population increase in 1 hour?

(1) The current population is 300,000 bacteria.

(2) The bacteria population doubles every 15 minutes.
1) is not sufficient

2) is sufficient.. let the current population be x, by 15 minutes it will be 2x, by half n hour mark it will be 4x, and in the end of the hour it will be 16x

% increase = (16x -x)100/x = 1500

B
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by thephoenix » Sat Feb 20, 2010 8:21 pm
gmatnmein2010 wrote:By what percent will the bacteria population increase in 1 hour?

(1) The current population is 300,000 bacteria.

(2) The bacteria population doubles every 15 minutes.
s1) insuff, as rate is not given

s2)now x
15------2x
30-------4x
45---------8x
60---------16x

% change=(16x-x)/x *100=1500 %

suff

IMO B

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by shashank.ism » Sat Feb 20, 2010 8:31 pm
gmatnmein2010 wrote:By what percent will the bacteria population increase in 1 hour?

(1) The current population is 300,000 bacteria.

(2) The bacteria population doubles every 15 minutes.
St. 1 insuff. we don't know the rate of growth of bacteria....so we can't calculate....
St. 2 : since The bacteria population doubles every 15 minutes. so bacteria, population will become 16x if we consider x as initial population
so % increase = (15x/x)x100 = [spoiler]1500% Ans B[/spoiler]
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by bhumika.k.shah » Sun Feb 21, 2010 7:59 am
A is clearly insufficient.

B . since its asking for %, its easy to take any #, plug in the value and get answers for 15mins , 30 mins , 45 mins and finally what we need - 1 hour.
u'll get the answer as 1500%

which is what we require.

Hence B is sufficient

IMO B

Hope this helps :)