Answer:
Step-by-step explanation:
The explicit formula for the n-th term of an arithmetic sequence is ...
an = a1 + d(n -1)
where a1 is the first term and d is the common difference.
The sequence of seat counts has a1=5 and d=10, so the explicit formula is ...
an = 5 +10(n -1)
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The 7th term is ...
a7 = 5 +10(7 -1) = 65
