You work for a roofing company and must order the correct number of tiles to complete the final side of the roof. It is in the shape of a trapezoid. The numbers of tiles in each row form a sequence. We know we will have 20 rows to complete the job. The first row has ten tiles. Each row has two more tiles than the previous row.

a. Is this sequence arithmetic or geometric? Explain.

b. How many tiles are needed for each of the first four rows?

c. Write the equation for the sequence in this situation.

d. How many tiles are in the fifteenth row?

e. How many total tiles will be needed to complete the job?

Answer:Part 1Part 2