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| Question 978184:  The doubling period of a baterial population is   10   minutes. At time  t = 110  minutes, the baterial population was 80000. Round your answers to at least 1 decimal place.
 What was the initial population at time  t = 0 ?
 Find the size of the baterial population after 3 hours
 Answer by Boreal(15235)
      (Show Source): 
You can put this solution on YOUR website! A=Ao(1+r)^t, where t=number of 10 minute intervals A/Ao=2=(1+r)^t
 ln of both sides
 0.693=t(ln(1+r)
 t=1
 0.6931=ln(1+r)
 2=(1+r); r=1
 80000=Ao(2)^11
 ln 80000=ln Ao+11 ln(2)
 11.2898=ln Ao + 7.623
 3.6667=ln Ao
 Take e of both sides.
 e=39.12 or 39, initially
 39[(2)^11]=79872, and with rounding, that is 80000
 after 3 hours, t=18
 39*2^18=
 10,223,616.  Note, must round down to 39 first, since can't have a fractional bacterium.
 
 
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