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Finding the Fourth Proportional to 800.80, 1,201.16 and 280.64

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Solution

The fourth proportional to 800.80, 1,201.16 and 280.64 is: 420.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    800.80 : 1,201.16 = 280.64 : x
  2. Step 2: Convert to fraction form
    800.80/1,201.16 = 280.64/x
  3. Step 3: Cross multiply
    800.80x = 1,201.16 × 280.64
  4. Step 4: Simplify right side
    800.80x = 337,093.54
  5. Step 5: Solve for x
    x = 337,093.54/800.80
  6. Step 6: Final answer
    x = 420.95

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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.