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Finding the Fourth Proportional to 605.20, 908.15 and 399.87

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Solution

The fourth proportional to 605.20, 908.15 and 399.87 is: 600.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    605.20 : 908.15 = 399.87 : x
  2. Step 2: Convert to fraction form
    605.20/908.15 = 399.87/x
  3. Step 3: Cross multiply
    605.20x = 908.15 × 399.87
  4. Step 4: Simplify right side
    605.20x = 363,135.40
  5. Step 5: Solve for x
    x = 363,135.40/605.20
  6. Step 6: Final answer
    x = 600.03

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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.