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Finding the Fourth Proportional to 658.29, 987.21 and 311.29

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Solution

The fourth proportional to 658.29, 987.21 and 311.29 is: 466.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.29 : 987.21 = 311.29 : x
  2. Step 2: Convert to fraction form
    658.29/987.21 = 311.29/x
  3. Step 3: Cross multiply
    658.29x = 987.21 × 311.29
  4. Step 4: Simplify right side
    658.29x = 307,308.60
  5. Step 5: Solve for x
    x = 307,308.60/658.29
  6. Step 6: Final answer
    x = 466.83

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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.