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Finding the Fourth Proportional to 418.40, 627.92 and 281.12

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Solution

The fourth proportional to 418.40, 627.92 and 281.12 is: 421.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.40 : 627.92 = 281.12 : x
  2. Step 2: Convert to fraction form
    418.40/627.92 = 281.12/x
  3. Step 3: Cross multiply
    418.40x = 627.92 × 281.12
  4. Step 4: Simplify right side
    418.40x = 176,520.87
  5. Step 5: Solve for x
    x = 176,520.87/418.40
  6. Step 6: Final answer
    x = 421.90

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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.