An auditorium has 28 seats in the front row. Each row behind the front has 3 more seats than the row directly in front of it. How many seats are there in the 11th row?

Mathematics · Middle School · Thu Feb 04 2021

Answered on

Formula Used:

a_n = a + (n-1)d

We have, a = 28, d = 3 and n =11

Substituting values in formula,  we get

a_11 = 28 + (11-1) 3

         = 28 + 10 × 3

         = 28  + 30

         = 58

 

Hence, there will be 58 seats in 11th row.