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Finding the Third Proportional to 129 and 311

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Solution

The third proportional to 129 and 311 is: 749.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    129 : 311 = 311 : x
  2. Step 2: Convert to fraction form
    129/311 = 311/x
  3. Step 3: Cross multiply
    129x = 311 × 311
  4. Step 4: Simplify right side
    129x = 96,721
  5. Step 5: Solve for x
    x = 96,721/129
  6. Step 6: Final answer
    x = 749.78

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Why These Related Problems?

These problems maintain the same ratio (2.41) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.