SOLUTION: The count in a bacteria culture was 500 after 10 minutes and 1700 after 35 minutes. Assuming the count grows exponentially, a). What was the initial size of the culture? b). Find

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Question 1111939: The count in a bacteria culture was 500 after 10 minutes and 1700 after 35 minutes. Assuming the count grows exponentially,
a). What was the initial size of the culture?
b). Find the doubling period.
c). Find the population after 65 minutes.
d). When will the population reach 11000?
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
y=ab%5Ex

system%28500=a%2Ab%5E10%2C1700=a%2Ab%5E35%29

17%2F5=b%5E25

b=1.0502
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a=1700%2Fb%5E35
a=1700%2F%281.0502%5E35%29
a=306 assumngthreesigfigs
highlight_green%28y=306%2A1.05%5Ex%29------------Model Equation
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a). What was the initial size of the culture?
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Initial size of culture probably 300.
(Computed to 306, but only two significant figures at best should be taken.)

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b). Find the doubling period.
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Starting with y=306%2A1.05%5Ex,
try 2=1%2A1.05%5Ex and solve for x.



You try the rest...

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c). Find the population after 65 minutes.
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d). When will the population reach 11000?
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