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Finding the Fourth Proportional to 638.91, 958.17 and 205.97

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Solution

The fourth proportional to 638.91, 958.17 and 205.97 is: 308.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.91 : 958.17 = 205.97 : x
  2. Step 2: Convert to fraction form
    638.91/958.17 = 205.97/x
  3. Step 3: Cross multiply
    638.91x = 958.17 × 205.97
  4. Step 4: Simplify right side
    638.91x = 197,352.30
  5. Step 5: Solve for x
    x = 197,352.30/638.91
  6. Step 6: Final answer
    x = 308.89

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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.