In the pond, the percentage of fish left after ten days is 4%.
Given that;
N(t) = Noe^-kt
Where;
N(t) = percentage of fish at time t
No = Initial percentage of fish
k = rate constant
t = time taken
Given that we had 100% fish population at the beginning, we can see that this reaction is first order.
The rate constant is obtained from;
When t = 5
19 = 100e^-5k
19/100 =e^-5k
0.19 = e^-5k
ln 0.19 = -5k
k = ln (0.19)/-5
k = 0.33
In ten days;
N(10) = 100e^-0.33(10)
N(10) = 4%
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