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Finding the Fourth Proportional to 512.20, 763.85 and 499.78

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Solution

The fourth proportional to 512.20, 763.85 and 499.78 is: 745.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    512.20 : 763.85 = 499.78 : x
  2. Step 2: Convert to fraction form
    512.20/763.85 = 499.78/x
  3. Step 3: Cross multiply
    512.20x = 763.85 × 499.78
  4. Step 4: Simplify right side
    512.20x = 381,756.95
  5. Step 5: Solve for x
    x = 381,756.95/512.20
  6. Step 6: Final answer
    x = 745.33

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.