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Finding the Third Proportional to 6.87 and 11.09

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Solution

The third proportional to 6.87 and 11.09 is: 17.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    6.87 : 11.09 = 11.09 : x
  2. Step 2: Convert to fraction form
    6.87/11.09 = 11.09/x
  3. Step 3: Cross multiply
    6.87x = 11.09 × 11.09
  4. Step 4: Simplify right side
    6.87x = 122.95
  5. Step 5: Solve for x
    x = 122.95/6.87
  6. Step 6: Final answer
    x = 17.90

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Why These Related Problems?

These problems maintain the same ratio (1.61) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.