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Finding the Third Proportional to 138.66 and 290.81

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Solution

The third proportional to 138.66 and 290.81 is: 609.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.66 : 290.81 = 290.81 : x
  2. Step 2: Convert to fraction form
    138.66/290.81 = 290.81/x
  3. Step 3: Cross multiply
    138.66x = 290.81 × 290.81
  4. Step 4: Simplify right side
    138.66x = 84,571.91
  5. Step 5: Solve for x
    x = 84,571.91/138.66
  6. Step 6: Final answer
    x = 609.94

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Why These Related Problems?

These problems maintain the same ratio (2.10) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.