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Finding the Fourth Proportional to 539.39, 809.33 and 386.30

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Solution

The fourth proportional to 539.39, 809.33 and 386.30 is: 579.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    539.39 : 809.33 = 386.30 : x
  2. Step 2: Convert to fraction form
    539.39/809.33 = 386.30/x
  3. Step 3: Cross multiply
    539.39x = 809.33 × 386.30
  4. Step 4: Simplify right side
    539.39x = 312,644.27
  5. Step 5: Solve for x
    x = 312,644.27/539.39
  6. Step 6: Final answer
    x = 579.62

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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.