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Finding the Fourth Proportional to 636.20, 878.02 and 387.54

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Solution

The fourth proportional to 636.20, 878.02 and 387.54 is: 534.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    636.20 : 878.02 = 387.54 : x
  2. Step 2: Convert to fraction form
    636.20/878.02 = 387.54/x
  3. Step 3: Cross multiply
    636.20x = 878.02 × 387.54
  4. Step 4: Simplify right side
    636.20x = 340,267.87
  5. Step 5: Solve for x
    x = 340,267.87/636.20
  6. Step 6: Final answer
    x = 534.84

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.