It would take about 57 hours for the number of spores to be less than 500 spores.
<h3>Exponential Function</h3>An exponential function is in the form:
y = abˣ
Where y,x are variables, a is the initial value of y and b is the multiplication factor.
Let y is the number of pores after x hours.
a = 6200, b = 100% - 20% = 0.8, hence to be less than 500 spores:
(x/5) * ln(0.8) < ln(0.08)
x > 56.4 hours
It would take about 57 hours for the number of spores to be less than 500 spores.
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