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Finding the Third Proportional to 128,909 and 279,320

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Solution

The third proportional to 128,909 and 279,320 is: 605,230.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    128,909 : 279,320 = 279,320 : x
  2. Step 2: Convert to fraction form
    128,909/279,320 = 279,320/x
  3. Step 3: Cross multiply
    128,909x = 279,320 × 279,320
  4. Step 4: Simplify right side
    128,909x = 78,019,662,400
  5. Step 5: Solve for x
    x = 78,019,662,400/128,909
  6. Step 6: Final answer
    x = 605,230.53

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Why These Related Problems?

These problems maintain the same ratio (2.17) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.