Question

a lawn is in the shape of a trapezoid with a height of 50 feet and bases of 60 feet and 140 feet. how many bags of fertilizer must be purchased to cover the lawn if each bag covers 2400 square feet? (round up to the nearest bag)

Explanation:

Step1: Calculate the area of the trapezoid lawn

Use the trapezoid - area formula $A=\frac{(a + b)h}{2}$, where $a = 60$ feet, $b = 140$ feet, and $h = 50$ feet.
$A=\frac{(60 + 140)\times50}{2}=\frac{200\times50}{2}=5000$ square feet.

Step2: Calculate the number of fertilizer bags

Divide the total area of the lawn by the area covered by each bag. Each bag covers 2400 square feet. Let $n$ be the number of bags. Then $n=\frac{5000}{2400}=\frac{25}{12}\approx2.083$.

Step3: Round up to the nearest bag

Since we can't buy a fraction of a bag, we round up. So $n = 3$.

Answer:

3