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Finding the Fourth Proportional to 801.25, 1,201.12 and 280.91

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Solution

The fourth proportional to 801.25, 1,201.12 and 280.91 is: 421.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    801.25 : 1,201.12 = 280.91 : x
  2. Step 2: Convert to fraction form
    801.25/1,201.12 = 280.91/x
  3. Step 3: Cross multiply
    801.25x = 1,201.12 × 280.91
  4. Step 4: Simplify right side
    801.25x = 337,408.92
  5. Step 5: Solve for x
    x = 337,408.92/801.25
  6. Step 6: Final answer
    x = 421.10

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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.