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Finding the Fourth Proportional to 512.09, 768.43 and 280.83

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Solution

The fourth proportional to 512.09, 768.43 and 280.83 is: 421.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    512.09 : 768.43 = 280.83 : x
  2. Step 2: Convert to fraction form
    512.09/768.43 = 280.83/x
  3. Step 3: Cross multiply
    512.09x = 768.43 × 280.83
  4. Step 4: Simplify right side
    512.09x = 215,798.20
  5. Step 5: Solve for x
    x = 215,798.20/512.09
  6. Step 6: Final answer
    x = 421.41

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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.