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Finding the Fourth Proportional to 638.89, 958.26 and 309.73

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Solution

The fourth proportional to 638.89, 958.26 and 309.73 is: 464.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.89 : 958.26 = 309.73 : x
  2. Step 2: Convert to fraction form
    638.89/958.26 = 309.73/x
  3. Step 3: Cross multiply
    638.89x = 958.26 × 309.73
  4. Step 4: Simplify right side
    638.89x = 296,801.87
  5. Step 5: Solve for x
    x = 296,801.87/638.89
  6. Step 6: Final answer
    x = 464.56

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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.