Question

Hi im working in math and have a hard time working through math questions can someone please EXPLAIN how to do this question please?

A new movie theater has stadium seating. The first row has 10 seats. Each additional row has 4 seats more than the row before it. How many seats are in the theater if there are 16 rows of seats?
Thx

Answer 1

this is representative of an arithmetic sequence .... a list of numbers that differ by some constant adder

Answer 2

row1 = 10
row2 = 10+4
row3 = 10 + 4 + 4
etc ...

Answer 3

if we notice a pattern in the 4s, there are n-1 4s in the nth row

row4 therefore has 10 + 4(3) seats
row5 has 10+ 4(4) seats and so on

Answer 4

oh, and if i read all the way thru it .... lol

add up all the rows to find the total number of seats

Answer 5

so,

10 + 4( 0)
+ 10 + 4( 1)
+ 10 + 4( 2)
+ 10 + 4( 3)
+ 10 + 4( 4)
...
+ 10 + 4( 16)
-------------
17(10) + 4(0+1+2+3+4+...+16)

Answer 6

so would it be 72