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Finding the Third Proportional to 128,135 and 280,408

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Solution

The third proportional to 128,135 and 280,408 is: 613,639.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    128,135 : 280,408 = 280,408 : x
  2. Step 2: Convert to fraction form
    128,135/280,408 = 280,408/x
  3. Step 3: Cross multiply
    128,135x = 280,408 × 280,408
  4. Step 4: Simplify right side
    128,135x = 78,628,646,464
  5. Step 5: Solve for x
    x = 78,628,646,464/128,135
  6. Step 6: Final answer
    x = 613,639.10

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Why These Related Problems?

These problems maintain the same ratio (2.19) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.