Problema Solution
in a theater with 30 rows the number increases by two with each successive row the front row has 15 seats Find the total seating capacity of the theater
Answer provided by our tutors
Let
1st row: 15 seats
2nd row: 15 + 2
3rd row: 15 + 2 + 2 = 15 + 2*2
4th row: 15 + 2*2 + 2 = 15 + 2*3
....
50th row = 15 + 2*29
15 + 15 + 2 + 15 + 2*2 + ... + 15 + 2*29 =
= 30*15 + 2(1 + 2 + 3 + ... + 29) =
= 450 + 2*(1/2)29(29 + 1) = 1320 seats
The total seating capacity of the theater is 1,320 seats.