A certain town has an area of 4.36 square miles. What is the area, in square yards, of this town?...
GMAT Problem-Solving and Data Analysis : (PS_DA) Questions
A certain town has an area of \(4.36\) square miles. What is the area, in square yards, of this town? (\(1 \text{ mile} = 1,760 \text{ yards}\))
404
7,674
710,459
13,505,536
1. TRANSLATE the problem information
- Given information:
- Town area: 4.36 square miles
- Conversion factor: 1 mile = 1,760 yards
- Need to find: area in square yards
2. INFER the conversion approach
- Key insight: When converting area measurements, we must square the linear conversion factor
- Since \(\mathrm{1\text{ mile} = 1,760\text{ yards}}\), then \(\mathrm{1\text{ square mile} = (1,760\text{ yards})^2}\)
- Strategy: First find square yards per square mile, then multiply by 4.36
3. Calculate the area conversion factor
- 1 square mile = \(\mathrm{(1,760)^2}\) square yards
- \(\mathrm{1,760^2 = 3,097,600}\) square yards per square mile (use calculator)
4. SIMPLIFY to find the final answer
- Town area = 4.36 square miles × 3,097,600 square yards per square mile
- \(\mathrm{4.36 \times 3,097,600 = 13,505,536}\) square yards (use calculator)
Answer: D. 13,505,536
Why Students Usually Falter on This Problem
Most Common Error Path:
Weak INFER skill: Students don't recognize that area conversions require squaring the linear conversion factor. They see "\(\mathrm{1\text{ mile} = 1,760\text{ yards}}\)" and think "\(\mathrm{1\text{ square mile} = 1,760\text{ square yards}}\)."
Using this incorrect reasoning: \(\mathrm{4.36 \times 1,760 = 7,673.6 \approx 7,674}\)
This may lead them to select Choice B (7,674)
Second Most Common Error:
Inadequate SIMPLIFY execution: Students understand the squaring concept but make calculation errors when computing \(\mathrm{1,760^2}\) or the final multiplication, especially if attempting these complex calculations without a calculator.
This leads to confusion and selecting an incorrect answer choice through computational mistakes.
The Bottom Line:
The key challenge is recognizing that area measurements involve two dimensions, so when you convert the linear dimension (miles to yards), the area conversion factor must be squared. This is a fundamental concept about how area units relate to linear units that many students haven't fully internalized.
404
7,674
710,459
13,505,536