An artist is arranging tiles in rows to decorate a wall. Each new row has 2 fewer tiles than the row below it. If the first row has 23 tiles how many tiles will be in the 7th row?

Answer 1

This is an arithmetic sequence
see : http://www.mathsisfun.com/algebra/sequences-sums-arithmetic.html
term n = a + d(n-1)
a = 23
d = -2

term 7 = 23 -2 (6)

= 11

Answer 2

Artist is arranging tiles and Rose decorate to decorate a wall each new row has two fewer tiles in the row below it if the first row has 23 tiles how many tiles will be in the seventh row

Answer 3

my anwer was 21

Answer 4

21