Question

The seats at a local baseball stadium are arranged so that each row has five more seats than the row in front of it. If there are four seats in the first row, how many total seats are in the first 24 rows? (2 points)

1,428
1,476
2,856
2,952

Answer 1

B

Explanation:

This is a summation problem. The difference is the same all the way up.

First we have to find the last term.

t24 = a + (n - 1)*d

a = 4

n = 24

d = 5

t24 = 4 + (24 - 1)*5

t24 = 4 + 23*5

t24 = 4 + 115

t24 = 119

Now you can calculate the total

Sum = (a + t24)*n/2

Sum = (4 + 119)*24/2

Sum = (4 + 119)*12

Sum = 123 * 12

Sum = 1476