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Finding the Fourth Proportional to 137.20, 205.86 and 68.73

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Solution

The fourth proportional to 137.20, 205.86 and 68.73 is: 103.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.20 : 205.86 = 68.73 : x
  2. Step 2: Convert to fraction form
    137.20/205.86 = 68.73/x
  3. Step 3: Cross multiply
    137.20x = 205.86 × 68.73
  4. Step 4: Simplify right side
    137.20x = 14,147.56
  5. Step 5: Solve for x
    x = 14,147.56/137.20
  6. Step 6: Final answer
    x = 103.12

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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.