Min jee wants to build a small patio using either brick or paver stones.
it will be 70 inches long and 49 inches wide. each brick covers an area of 3 1/2 inches by 7 1/2 inches, and cost $0.59.
each paver covers an areas 8.4 inches by 8.4 inches and costs $1.88. what would be less expensive to use, and by how much?

Brick = 3.5 in by 7.5 in and costs $0.59
Paver = 8.4 in by 8.4 in and costs $1.88

The small patio's area = 3430 square inches
The Area of 1 Brick = 26.25 square inches
The Area of 1 Paver = 70.56 square inches

The # of Bricks to complete the Patio will be:

Patio's Area / the Area of 1 Brick = # of Bricks to complete the patio
3430 square inches / 26.25 square inches = 130.67 = 131

Then, multiply the # of Bricks to complete the patio by the amount that 1 brick costs:

131 * $0.59 = $77.29

It will take $77.29 to complete the Patio with bricks. 

The # of Pavers to complete the Patio:

Patio's Area / the Area of 1 Paver =  # of Pavers to complete the Patio
3430 square inches / 70.56 square inches = 48.6 = 49

Then, multiply the # of Pavers to complete the patio by the amount that 1 Paver costs:

49 * $1.88 = $92.12

Cost of Bricks to complete Patio = $77.29
Cost of Pavers to complete Patio = $92.12

To conclude, Bricks would cost less by $14.83.

The coefficient, 5 represents the length in relation to the problem.