In order to know what is the reasonable amount of tile for Mandana to order, you have to divide the choices with the area of the floor and deduct with 1 and multiply by 100. You have to assess if the answer you will get will fall between 15% and 20% which is the goal of Mandana.
a. 131/116.9 = (1.1206 – 1) x 100 = 12.06%, this does not fall between 15% and 20%
b. 138/116.9 = (1.1805 – 1) x 100 = 18.05%, this fall between 15% and 20%
c. 133/116.9 = (1.1377 – 1) x 100 = 13.77%, this does not fall between 15% and 20%
d. 141/116.9 = (1.2062 – 1) x 100 = 20.62%, this does not fall between 15% and 20%
Therefore, the reasonable amount of tile for Madana to order that is between 15% and 20% extra of the materials is 138 square feet.
