Answer:
Step-by-step explanation:
We have the sequence: 50, 54, 58, ....
The sum to n terms is a + (n - 1)d....where a is the first term and d is the difference between terms. Hence, a = 50 and d = 4
so, f(n) = 50 + 4(n - 1) => 4n + 46
Hence, in row 20 we have 4(20) + 46 => 126 seats
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