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Finding the Fourth Proportional to 103.20, 154.87 and 39.12

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Solution

The fourth proportional to 103.20, 154.87 and 39.12 is: 58.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.20 : 154.87 = 39.12 : x
  2. Step 2: Convert to fraction form
    103.20/154.87 = 39.12/x
  3. Step 3: Cross multiply
    103.20x = 154.87 × 39.12
  4. Step 4: Simplify right side
    103.20x = 6,058.92
  5. Step 5: Solve for x
    x = 6,058.92/103.20
  6. Step 6: Final answer
    x = 58.71

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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.