Question 1129988:  The Land O’ Lakes High School auditorium has exactly 26 rows of seats. The rows are labeled, in order, from the front of the auditorium to the back from A through Z. There are 8 seats in the row A. Each row after the first row has two more seats than the previous row. There are 10 seats in row B, 12 seats in row C and so on. How many seats are there in row Z?
 
For this answer, I have 58 seats.
 
What is the total number of seats in the Land O’ Lakes High School auditorium?
 
For this answer, I have 1508 seats
 
 
Land O’ Lakes High School collected $2860 from ticket sales for the winter concert. A ticket was sold for every seat in the auditorium, resulting in a sold out concert. If the price of an adult ticket was three times the price of a student ticket, and twice as many student tickets were sold as adult tickets, what was the price of a student ticket?
 
I cannot figure out this last one.  
 Found 3 solutions by  Boreal, math_helper, rothauserc: Answer by Boreal(15235)      (Show Source): 
You can  put this solution on YOUR website! sum=(n/2)(2a+(n-1)d)=13(16+(25)(2))=13*66=858 seats
 
student=x 
adult=858-x 
x=2(858-x) 
3x=1716 
x=572 student tickets and 286 adult tickets 
student ticket costs y 
adult ticket costs 3y 
572y+286(3y)=2860 
1430y=2860 
y=$2, student ticket cost 
3y=$6, adult ticket cost 
 Answer by math_helper(2461)      (Show Source): 
You can  put this solution on YOUR website! Row Z having 58 seats is correct.  Good work.  
 
Not sure what you did to find 1508 seats, since you did not show your work.   Using (average number of seats per row) x (number of rows):    correct total number of seats is  ((8 + 58)/2)*26 = 858     
 
 
For the last part: 
let A = number of adult tickets sold 
let S = number of student tickets sold 
  
(eq 1)  A + S = 858    (a ticket for every seat was sold) 
(eq 2)  S = 2A 
The total ticket sales information will be used later… 
 
Solve to get 
A = 286  
S = 572 
 
Now, incorporating the total ticket sales: 
Let x = price of student ticket, then 3x = price of an adult ticket  
2860 = A*(3x) + S*(x)  
 
Plug in for A and S, then solve for x to get the price of a student ticket  ($2)
 
 
 
 
 Answer by rothauserc(4718)      (Show Source): 
You can  put this solution on YOUR website! this is an arithmetic sequence 
: 
x(n) = a +2(n-1) 
: 
a = 8 
: 
x(26) = 8 +2(26-1) = 58 
: 
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58 seats in row Z 
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: 
use the formula for the sum of the elements of an arithmetic sequence 
: 
sum = (n/2)*(2a +(n-1)d), where n=26, a=8, d=2 
: 
sum = (26/2)*(2*8 +(26-1)*2) = 858 
: 
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there are 858 seats in the auditorium  
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: 
let a be the number of adult tickets, then number of student tickets is 2a 
: 
1) a +2a = 858 
: 
3a = 858 
: 
a = 286 
: 
286 adult tickets were sold and 572 student tickets were sold 
: 
let x be the cost of a student ticket, then 3x is the cost of an adult ticket 
: 
286*(3x) +572x = 2860 
: 
858x +572x = 2860 
: 
1430x = 2860 
: 
x = 2 
: 
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the student ticket costs $2 
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