The population of the Bulbul birds at the start of the migration season is 1800.
An exponential function is given by:
y = abˣ
Let y, x are variables, a is the initial value and b is the multiplication factor.
Let P be the population of the bird t days since the start of the migration season.
[tex]P=1350+400(1.25)^{-t}\\\\At\ the\ start\ of\ the\ season(t=0):\\\\P=1350+400(1.25)^{-0}\\\\P=1350+450=1800[/tex]
The population of the Bulbul birds at the start of the migration season is 1800.
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