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Finding the Fourth Proportional to 638.25, 956.28 and 418.74

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Solution

The fourth proportional to 638.25, 956.28 and 418.74 is: 627.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.25 : 956.28 = 418.74 : x
  2. Step 2: Convert to fraction form
    638.25/956.28 = 418.74/x
  3. Step 3: Cross multiply
    638.25x = 956.28 × 418.74
  4. Step 4: Simplify right side
    638.25x = 400,432.69
  5. Step 5: Solve for x
    x = 400,432.69/638.25
  6. Step 6: Final answer
    x = 627.39

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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.