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Finding the Fourth Proportional to 490.36, 676.71 and 280.55

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Solution

The fourth proportional to 490.36, 676.71 and 280.55 is: 387.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.36 : 676.71 = 280.55 : x
  2. Step 2: Convert to fraction form
    490.36/676.71 = 280.55/x
  3. Step 3: Cross multiply
    490.36x = 676.71 × 280.55
  4. Step 4: Simplify right side
    490.36x = 189,850.99
  5. Step 5: Solve for x
    x = 189,850.99/490.36
  6. Step 6: Final answer
    x = 387.17

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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.