Answer
Initial amount $a=575$
Rate of decay $r=60\%$
At $t=3,y=36.8$.$
Work Step by Step
The given expression is
$\Rightarrow y=575(1-0.6)^t$
The standard form of an exponential decay function is
$y=a(1-r)^t$
Initial amount $a=575$
Rate of decay $r=0.6=60\%$
Substitute $3$ for $t$.
$\Rightarrow y=575(1-0.6)^3$
Simplify.
$\Rightarrow y=575(0.4)^3$
Evaluate the power.
$\Rightarrow y=575(0.064)$
Simplify.
$\Rightarrow y=36.8$.
