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Finding the Fourth Proportional to 138.61, 209.39 and 137.50

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Solution

The fourth proportional to 138.61, 209.39 and 137.50 is: 207.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.61 : 209.39 = 137.50 : x
  2. Step 2: Convert to fraction form
    138.61/209.39 = 137.50/x
  3. Step 3: Cross multiply
    138.61x = 209.39 × 137.50
  4. Step 4: Simplify right side
    138.61x = 28,789.91
  5. Step 5: Solve for x
    x = 28,789.91/138.61
  6. Step 6: Final answer
    x = 207.70

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.