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Finding the Fourth Proportional to 519.78, 778.41 and 398.28

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Solution

The fourth proportional to 519.78, 778.41 and 398.28 is: 596.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    519.78 : 778.41 = 398.28 : x
  2. Step 2: Convert to fraction form
    519.78/778.41 = 398.28/x
  3. Step 3: Cross multiply
    519.78x = 778.41 × 398.28
  4. Step 4: Simplify right side
    519.78x = 310,025.13
  5. Step 5: Solve for x
    x = 310,025.13/519.78
  6. Step 6: Final answer
    x = 596.45

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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.