The total cost for 20 tickets is (a) $14.50
The piecewise function is given as:
[tex]C(t) = \left[\begin{array}{ccc}\$18.50&1 \le t < 12 & \\\$16.00&12 \le t < 20 & \\\$14.50&20 \le t &\end{array}\right[/tex]
To determine the value of a piece function, we simply make reference to the domain or interval of the function.
For a total cost of 20 tickets, it means that the value of t is 20.
This is represented as:
[tex]t = 20[/tex]
The value of t = 20 falls under the domain [tex]20 \le t[/tex], and the corresponding function is:
[tex]C(t) = 14.50[/tex]
Hence, the total cost for 20 tickets is (a) $14.50
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