a. If every student who attends shares the facility cost equally, the function model will be 1200/N
domain : 1 ≤ N ≤ (312 - additional adult chaperones) N ∈ Z
1200/N ≤ 7.50
1200 / 7.50 ≤ N
N ≥ 1200/7.5
N ≥ 160
More than 160 students must attend to make the cost per student no more than $ 7.50
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