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Finding the Fourth Proportional to 490.42, 676.77 and 280.60

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Solution

The fourth proportional to 490.42, 676.77 and 280.60 is: 387.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.42 : 676.77 = 280.60 : x
  2. Step 2: Convert to fraction form
    490.42/676.77 = 280.60/x
  3. Step 3: Cross multiply
    490.42x = 676.77 × 280.60
  4. Step 4: Simplify right side
    490.42x = 189,901.66
  5. Step 5: Solve for x
    x = 189,901.66/490.42
  6. Step 6: Final answer
    x = 387.22

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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.