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Finding the Fourth Proportional to 539.20, 809.25 and 385.50

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Solution

The fourth proportional to 539.20, 809.25 and 385.50 is: 578.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    539.20 : 809.25 = 385.50 : x
  2. Step 2: Convert to fraction form
    539.20/809.25 = 385.50/x
  3. Step 3: Cross multiply
    539.20x = 809.25 × 385.50
  4. Step 4: Simplify right side
    539.20x = 311,965.88
  5. Step 5: Solve for x
    x = 311,965.88/539.20
  6. Step 6: Final answer
    x = 578.57

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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.