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Finding the Fourth Proportional to 638.43, 956.85 and 272.79

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Solution

The fourth proportional to 638.43, 956.85 and 272.79 is: 408.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.43 : 956.85 = 272.79 : x
  2. Step 2: Convert to fraction form
    638.43/956.85 = 272.79/x
  3. Step 3: Cross multiply
    638.43x = 956.85 × 272.79
  4. Step 4: Simplify right side
    638.43x = 261,017.75
  5. Step 5: Solve for x
    x = 261,017.75/638.43
  6. Step 6: Final answer
    x = 408.84

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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.