SOLUTION: A certain bacteria population is known to doubles every 90 minutes. Suppose that there are initially 160 bacteria. What is the size of the population after t hours?

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Question 978185: A certain bacteria population is known to doubles every 90 minutes. Suppose that there are initially 160 bacteria.
What is the size of the population after t hours?
Found 2 solutions by Alan3354, Boreal:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
A certain bacteria population is known to doubles every 90 minutes. Suppose that there are initially 160 bacteria.
What is the size of the population after t hours?
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After t hours:
= 160%2A2%5E%28t%2F1.5%29
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The exponent is t/1.5 or 2t/3

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
A=160(1+r)^t
320/160=2=(1+r)^t
0.693=t ln (1 +r)
0.693/1.5 = ln (1+r)
0.462=ln (1+r)
raise to e power both sides
1.5872=1+r
r=0.5872
A=160(1.5872)^t ANSWER.
Expect quadrupling in 180 minutes or t=3
A=160(1.5872)^3=639.75 or rounded to 640.