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Finding the Fourth Proportional to 800.31, 1,200.83 and 389.85

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Solution

The fourth proportional to 800.31, 1,200.83 and 389.85 is: 584.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    800.31 : 1,200.83 = 389.85 : x
  2. Step 2: Convert to fraction form
    800.31/1,200.83 = 389.85/x
  3. Step 3: Cross multiply
    800.31x = 1,200.83 × 389.85
  4. Step 4: Simplify right side
    800.31x = 468,137.12
  5. Step 5: Solve for x
    x = 468,137.12/800.31
  6. Step 6: Final answer
    x = 584.94

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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.