Praxis Core Academic Skills for Educators: Mathematics (5733)Number and QuantityMedium
A carpenter needs to cut boards that are each 2 feet 8 inches long. If he has a supply of wood totaling 40 feet, how many full boards can he cut?
- A14 boards
- B15 boards
- C13 boards
- D12 boards
Show answer & explanationAnswer & explanation
Correct answer: B. 15 boards
First, convert all measurements to a single unit, such as inches. One board is 2 feet * 12 inches/foot + 8 inches = 24 + 8 = 32 inches. The total supply is 40 feet * 12 inches/foot = 480 inches. Divide the total supply by the length of one board: 480 inches / 32 inches/board = 15 boards. Since the question asks for 'full' boards, any remainder is ignored.
Why the other options are wrong
- A. This is incorrect; it might result from a miscalculation in conversion or division.
- C. This is incorrect; it might result from a miscalculation in conversion or division.
- D. This is incorrect; it might result from a miscalculation in conversion or division.
Unit Conversion (Length)
The process of converting a measurement from one unit of length to another, often using conversion factors.
- 1 foot = 12 inches.
- Consistency in units is crucial for accurate calculations.
- When dividing to find 'how many', only whole numbers (full items) are considered.
Memory trick: Feet to inches, multiply by twelve; inches back to feet, divide yourself!