One 15 pound bag of lawn fertilizer covers 350 square feet. Garden Depot sells full bags of fertilizer for $7.89. What will the cost of enough fertilizer to cover a 42 foot by 80 foot lawn?

Area to be covered = 42(80) or 3360 f^2

number of bags = 3360/350
= 9.6
but you can't buy a partial bag, so he needs 10 bags, which will cost $78.90

To calculate the cost of enough fertilizer to cover a 42 foot by 80 foot lawn, we need to find the total area of the lawn and then determine how many bags of fertilizer are required to cover that area.

Step 1: Calculate the total area of the lawn
Area = length * width
Area = 42 feet * 80 feet
Area = 3360 square feet

Step 2: Determine the number of bags of fertilizer required
Coverage per bag = 350 square feet
Number of bags = Area / Coverage per bag
Number of bags = 3360 square feet / 350 square feet
Number of bags ≈ 9.6 bags

Since you cannot purchase a fraction of a bag, you will need to round up to the nearest whole number. Therefore, you need 10 bags of fertilizer to cover your lawn.

Step 3: Calculate the cost of the fertilizer
Cost per bag = $7.89
Total cost = Number of bags * Cost per bag
Total cost = 10 bags * $7.89
Total cost = $78.90

The cost of enough fertilizer to cover a 42 foot by 80 foot lawn is approximately $78.90.