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Finding the Fourth Proportional to 819.37, 1,229.23 and 380.30

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Solution

The fourth proportional to 819.37, 1,229.23 and 380.30 is: 570.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    819.37 : 1,229.23 = 380.30 : x
  2. Step 2: Convert to fraction form
    819.37/1,229.23 = 380.30/x
  3. Step 3: Cross multiply
    819.37x = 1,229.23 × 380.30
  4. Step 4: Simplify right side
    819.37x = 467,468.36
  5. Step 5: Solve for x
    x = 467,468.36/819.37
  6. Step 6: Final answer
    x = 570.52

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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.