The form of the exponential growth/decay function is
[tex]f(x)=a(1\pm r)^x[/tex]a is the initial amount
r is the rate of growth/decay per x years
We use + with growth and - with decay
Since the given function is
[tex]f(t)=2700(1.6)^{7t}[/tex]Where t is time per week
Compare the two functions
[tex]\begin{gathered} a=2700 \\ (1+r)=1.6 \\ x=7t \end{gathered}[/tex]Since 1.6 is greater than 1, then
The function is growth
Equate 1.6 by (1 + r) to find r
[tex]\begin{gathered} 1+r=1.6 \\ \\ 1-1+r=1.6-1 \\ \\ r=0.6 \end{gathered}[/tex]Change it to percent by multiplying it by 100%
[tex]\begin{gathered} r=0.6\times100\text{ \%} \\ \\ r=60\text{ \%} \end{gathered}[/tex]Since x = 7t then the time is every 7 weeks
The answer is
The function is growing exponentially at a rate of 60% every 7 weeks