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Finding the Fourth Proportional to 819.85, 1,230.30 and 490.54

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Solution

The fourth proportional to 819.85, 1,230.30 and 490.54 is: 736.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    819.85 : 1,230.30 = 490.54 : x
  2. Step 2: Convert to fraction form
    819.85/1,230.30 = 490.54/x
  3. Step 3: Cross multiply
    819.85x = 1,230.30 × 490.54
  4. Step 4: Simplify right side
    819.85x = 603,505.21
  5. Step 5: Solve for x
    x = 603,505.21/819.85
  6. Step 6: Final answer
    x = 736.12

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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.