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Finding the Fourth Proportional to 138.10, 207.30 and 137.09

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Solution

The fourth proportional to 138.10, 207.30 and 137.09 is: 205.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.10 : 207.30 = 137.09 : x
  2. Step 2: Convert to fraction form
    138.10/207.30 = 137.09/x
  3. Step 3: Cross multiply
    138.10x = 207.30 × 137.09
  4. Step 4: Simplify right side
    138.10x = 28,417.72
  5. Step 5: Solve for x
    x = 28,417.72/138.10
  6. Step 6: Final answer
    x = 205.78

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.