Given:
Investment = $400
simple interest rate = 16%
The simple interest formula is given as:
[tex]\begin{gathered} A\text{ = P\lparen1 + rt\rparen} \\ Where\text{ A is the future value} \\ P\text{ is the principal} \\ \text{ r is the rate of interest} \\ and\text{ t is the time in years} \end{gathered}[/tex]
Substituting the given values:
[tex]\begin{gathered} A\text{ = 400\lparen1 + 0.16}\times t) \\ =\text{ 400\lparen1 + 0.16t\rparen} \end{gathered}[/tex]
Hence, the function is:
[tex]A\text{ = 400\lparen1 + 0.16t\rparen}[/tex]
The sketch of the function is shown below:
