GED Mathematical Reasoning TestQuantitative Problem Solving with MeasurementMedium
A farmer is planning to build a rectangular fence around a new pasture. The pasture is 150 feet long and 75 feet wide. If fencing material costs $2.50 per foot, what is the total cost of the fence?
- A$562.50
- B$2,250
- C$375
- D$1,125
Show answer & explanationAnswer & explanation
Correct answer: D. $1,125
First, calculate the perimeter of the rectangular pasture using the formula P = 2(L + W). P = 2(150 feet + 75 feet) = 2(225 feet) = 450 feet. Then, multiply the total length of fencing by the cost per foot: 450 feet * $2.50/foot = $1,125.
Why the other options are wrong
- A. This would be the cost if only the area (L*W) was calculated and then multiplied by the cost, which is incorrect for fencing.
- B. This would be the result of a significant overestimation, possibly multiplying the perimeter by 5 instead of 2.5.
- C. This would be the cost if only one length and one width were added and multiplied by the cost, or a calculation error.
Perimeter of a Rectangle
The perimeter of a rectangle is the total distance around its outer edge, calculated by adding twice its length and twice its width.
- Formula: P = 2(L + W) or P = 2L + 2W
- Measured in linear units (e.g., feet, meters).
- Represents the boundary of a 2D shape.
Memory trick: Length plus width, then double that, multiply by cost, and that's that!