Last one
Because you have to substitute it
So you do X times 2 - 16 = 0
And the only X that works is the last one cause 8 X 2 = 16 and 16 -16=0
<span>This is an arithmetic progression, i.e. 16,18,20,22,24,26,28.......... where 16 is the number of people seats in 1st row, 18 seats in second row, 20 seats in third row and so on. The Total number of seats in 20 rows = n/2{2a+(n-1)d}. Here, d = 2 , n =20, a = 16. Thus, Sum = 10 {32+ 19*2} = 10 {70} = 700 seats in total. </span>
The least common denominator is 2
It would most likely take 3-4 hours, maybe even 5.
