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Finding the Third Proportional to 128,805 and 280,520

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Solution

The third proportional to 128,805 and 280,520 is: 610,934.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    128,805 : 280,520 = 280,520 : x
  2. Step 2: Convert to fraction form
    128,805/280,520 = 280,520/x
  3. Step 3: Cross multiply
    128,805x = 280,520 × 280,520
  4. Step 4: Simplify right side
    128,805x = 78,691,470,400
  5. Step 5: Solve for x
    x = 78,691,470,400/128,805
  6. Step 6: Final answer
    x = 610,934.90

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Why These Related Problems?

These problems maintain the same ratio (2.18) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.