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Finding the Fourth Proportional to 489.96, 676.12 and 280.12

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Solution

The fourth proportional to 489.96, 676.12 and 280.12 is: 386.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.96 : 676.12 = 280.12 : x
  2. Step 2: Convert to fraction form
    489.96/676.12 = 280.12/x
  3. Step 3: Cross multiply
    489.96x = 676.12 × 280.12
  4. Step 4: Simplify right side
    489.96x = 189,394.73
  5. Step 5: Solve for x
    x = 189,394.73/489.96
  6. Step 6: Final answer
    x = 386.55

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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.