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Finding the Fourth Proportional to 638.85, 958.14 and 205.89

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Solution

The fourth proportional to 638.85, 958.14 and 205.89 is: 308.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.85 : 958.14 = 205.89 : x
  2. Step 2: Convert to fraction form
    638.85/958.14 = 205.89/x
  3. Step 3: Cross multiply
    638.85x = 958.14 × 205.89
  4. Step 4: Simplify right side
    638.85x = 197,271.44
  5. Step 5: Solve for x
    x = 197,271.44/638.85
  6. Step 6: Final answer
    x = 308.79

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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.