Answer:
27 calls
Step-by-step explanation:
Let T(x) represent total sales.
Then T(x) = $150 + ($2/call)x, where x is the number of calls made.
If T(x) = $204, we can solve for x, the number of calls made:
$204 = $150 + ($2/call)x, or
$ 54
----------- = 27 calls
$2/call