A swimming pool whose dimensions are tile is $3 a square foot, determine the cost to re-tile the border of the pool

Question

A swimming pool whose dimensions are 20 ft by 30 ft, has a five-foot tile border around it. If the cost of tile is $3 a square foot, determine the cost to re-tile the border of the pool.

Answer 1

First, it helps to draw a picture for this problem. 

I drew a rectangle and labeled it 20ft by 30 ft. 

 

Then I drew the rectangle around the pool which extends out 5ft from the pool on all sides. 

 

The sides of the new rectangle are now 30ft by 40 ft. (Because we add 5ft on each end of the pool for the border.)

 

Now we have to find the area of the border. 

To do that we use the area of a rectangle formula which is A = length * width. 

 

Area = 30ft * 40ft

Area = 1200ft²

 

Now subtract the area of the pool from the area of the big triangle, because thdoesn'tt doesnt need to be tiled. Just the space between the two rectangles.

 

Area of the pool = 20ft * 30ft

Area = 600ft²

 

1200ft² - 600ft² = 600ft²

 

Great! Now we have the area of the tile. 

Now we must find the total cost of the new tile.

 

The tile is $3 per square foot.

 

600ft² * $3 = $1800

 

$1800 is the final answer!

 

Answer 2

So, since the border is on all 4 sides, we have a pool and border measuring 30 x 40 = 1200 sq ft.

 

The pool itself is 20 x 30 = 600 sq ft.

 

1200 - 600 = 600 sq ft of border

 

600(3) = $1800 for tile