Answer:
there are 84 seats in the second to the last row
Step-by-step explanation:
Given that
each row has two fewer seats than the row behind it
It means that
if first row has x seats then
no of seat in second row has (x-2) seats.
and similarly
no of seat in third row =no of seat in second row - 2seats.
no of seat in third row = (x-2) seat - 2 seats = x - 4 seats
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Given that
last row has 80 seats
let the number of seat in first to the last row be x
then number of seat in last row = x-2
we know number of seat in last row = 80
thus
x - 2 = 80
x = 82
Thus,
the number of seat in first to the last row is 82
Similarly let the number of seat in second to the last row be y
then number of seat in first to the last row = y-2
since number of seat in first to the last row is 82
thus
y-2 = 82
y = 82 + 2 = 84
Thus, there are 84 seats in the second to the last row.
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