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March 18th, 2017, 06:36 PM   #1
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I do not think enough info or is given or is abstract

Question 11
Within the first ten years of construction the population of rats in a sewer system can be modelled by the equation N=N_0 e^kt. 2 years after construction there are 118 rats and 4 years after construction there are 1392 rats.

a) Show that k≈1.234 (4 marks)








b) How many rats were there originally? (1 mark)




c) When will the population of rats reach 10,000? Give your answer to the nearest month (2 marks)

Edit the N is big and 0 small like a log for example
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March 18th, 2017, 06:43 PM   #2
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$N = N_0 e^{kt}$

$1392 = N_0e^{4k}$

$118 = N_0e^{2k}$

divide the first equation by the second ...

$\dfrac{1392}{118} = e^{2k}$ ... use logs to determine $k$, then use either of the original equations to determine $N_0$

once you have $k$ and $N_0$, determining $t$ when $N=10000$ should be no problemo.
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March 18th, 2017, 07:46 PM   #3
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Thank you Skeeter so much the N0 was rly confusing me
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