Question

A concert hall has 30 rows of seats with 20 seats in the 1st row, 22 in the 2nd row, 24 in the 3rd row, and so on. The price per ticket is $20. All the seats are sold. How much money does the concert hall get?

Answer 1

Answer: $1,220 so I hope that answers your question/is correct

Answer 2

Answer:

Step-by-step explanation:

First of all, how many seats are there?

a1 = 20

d = 2

n = 30

L = a1 + (n - 1)*d

L = 20 + (30 - 1) * 2

L = 20 + 29*2

L = 20 + 58

L = 78

Now we have to sum the first row to the 30th row

Sum = (a1 + a30)(30)/2

Sum = (20 + 78)*30/2

Sum = 98 *15

Sum = 1470

amount = 20*1470 = 29400