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Finding the Fourth Proportional to 539.47, 809.44 and 418.78

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Solution

The fourth proportional to 539.47, 809.44 and 418.78 is: 628.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    539.47 : 809.44 = 418.78 : x
  2. Step 2: Convert to fraction form
    539.47/809.44 = 418.78/x
  3. Step 3: Cross multiply
    539.47x = 809.44 × 418.78
  4. Step 4: Simplify right side
    539.47x = 338,977.28
  5. Step 5: Solve for x
    x = 338,977.28/539.47
  6. Step 6: Final answer
    x = 628.35

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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.