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Finding the Third Proportional to 8.72 and 12.09

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Solution

The third proportional to 8.72 and 12.09 is: 16.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    8.72 : 12.09 = 12.09 : x
  2. Step 2: Convert to fraction form
    8.72/12.09 = 12.09/x
  3. Step 3: Cross multiply
    8.72x = 12.09 × 12.09
  4. Step 4: Simplify right side
    8.72x = 146.26
  5. Step 5: Solve for x
    x = 146.26/8.72
  6. Step 6: Final answer
    x = 16.78

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.