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Finding the Fourth Proportional to 490.20, 676.40 and 280.34

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Solution

The fourth proportional to 490.20, 676.40 and 280.34 is: 386.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.20 : 676.40 = 280.34 : x
  2. Step 2: Convert to fraction form
    490.20/676.40 = 280.34/x
  3. Step 3: Cross multiply
    490.20x = 676.40 × 280.34
  4. Step 4: Simplify right side
    490.20x = 189,621.98
  5. Step 5: Solve for x
    x = 189,621.98/490.20
  6. Step 6: Final answer
    x = 386.83

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.