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Finding the Fourth Proportional to 403.78, 559.83 and 381.90

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Solution

The fourth proportional to 403.78, 559.83 and 381.90 is: 529.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    403.78 : 559.83 = 381.90 : x
  2. Step 2: Convert to fraction form
    403.78/559.83 = 381.90/x
  3. Step 3: Cross multiply
    403.78x = 559.83 × 381.90
  4. Step 4: Simplify right side
    403.78x = 213,799.08
  5. Step 5: Solve for x
    x = 213,799.08/403.78
  6. Step 6: Final answer
    x = 529.49

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.