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Finding the Fourth Proportional to 138.27, 205.98 and 129.87

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Solution

The fourth proportional to 138.27, 205.98 and 129.87 is: 193.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.27 : 205.98 = 129.87 : x
  2. Step 2: Convert to fraction form
    138.27/205.98 = 129.87/x
  3. Step 3: Cross multiply
    138.27x = 205.98 × 129.87
  4. Step 4: Simplify right side
    138.27x = 26,750.14
  5. Step 5: Solve for x
    x = 26,750.14/138.27
  6. Step 6: Final answer
    x = 193.46

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.