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Finding the Fourth Proportional to 539.70, 809.49 and 215.09

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Solution

The fourth proportional to 539.70, 809.49 and 215.09 is: 322.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    539.70 : 809.49 = 215.09 : x
  2. Step 2: Convert to fraction form
    539.70/809.49 = 215.09/x
  3. Step 3: Cross multiply
    539.70x = 809.49 × 215.09
  4. Step 4: Simplify right side
    539.70x = 174,113.00
  5. Step 5: Solve for x
    x = 174,113.00/539.70
  6. Step 6: Final answer
    x = 322.61

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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.