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Finding the Fourth Proportional to 819.40, 1,227.56 and 408.32

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Solution

The fourth proportional to 819.40, 1,227.56 and 408.32 is: 611.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    819.40 : 1,227.56 = 408.32 : x
  2. Step 2: Convert to fraction form
    819.40/1,227.56 = 408.32/x
  3. Step 3: Cross multiply
    819.40x = 1,227.56 × 408.32
  4. Step 4: Simplify right side
    819.40x = 501,237.30
  5. Step 5: Solve for x
    x = 501,237.30/819.40
  6. Step 6: Final answer
    x = 611.71

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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.