I need help on example 3. What do I multiply by? Explain.

Answer:
The relationship is not proportional.
Step-by-step explanation:
You multiply the number of tickets by $7, then add $3 for each of the number of orders that represents.
If you make 1 order of 4 tickets, the total cost is $7×4 + $3 = $31.
If you make 1 order of 1 ticket, the total cost is $7×1 + $3 = $10.
If you make 3 orders of 3 tickets each, then the cost is 3×($7×3 + $3) = $72.
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The question is not helpful, because it doesn't tell you how many orders you are making, or how many tickets are in each order. If you assume 1 order of varying numbers of tickets, you can fill in the table like this:
[tex]\begin{array}{lcccc}\text{cost (\$)}&10&17&24&31\\\text{tickets ordered}&1&2&3&4\end{array}[/tex]