Question

Christina wants to compute the cost of tiling the floor in her bathroom. The floor measures 7 feet 6 inches by 8 feet 10 inches. Each tile covers 1 square foot. —A box of 45 tiles costs $35.95.
(Christina is buying 2 boxes)

What is the cost of the tile needed for this project?



I got an answer of $71.9. Is that correct?

Answer 1

Answer:

Two boxes will cost $\ 35.95\cdot 2=\ 71.9.$ The cost of one tile is approximately $\dfrac{\ 71.9}{67}\approx \ 1.08.$

Step-by-step explanation:

Note that 1 ft = 12 in, then

$7\ ft\ 6\ in=7\cdot 12+6\ in =90\ in,\\ \\8\ ft\ 10\ in=8\cdot 12+10\ in=106\ in.$

The area of the floor is

$90\cdot 106=9540\ in^2.$

Now

$1\ ft^2=144\ in^2,$

then

144 sq. in - 1 tile,

9540 sq. in - x tiles.

Mathematically,

$\dfrac{144}{9540}=\dfrac{1}{x},\\ \\x=\dfrac{9540}{144}=66.25$

tiles is needed to cover the floor (67 full tiles).

Each box of tiles contains 45 tiles, so Cristina has to buy 2 boxes. These two boxes will cost $\ 35.95\cdot 2=\ 71.9.$ The cost of one tile is approximately $\dfrac{\ 71.9}{67}\approx \ 1.08.$