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Finding the Fourth Proportional to 641.60, 961.68 and 519.60

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Solution

The fourth proportional to 641.60, 961.68 and 519.60 is: 778.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.60 : 961.68 = 519.60 : x
  2. Step 2: Convert to fraction form
    641.60/961.68 = 519.60/x
  3. Step 3: Cross multiply
    641.60x = 961.68 × 519.60
  4. Step 4: Simplify right side
    641.60x = 499,688.93
  5. Step 5: Solve for x
    x = 499,688.93/641.60
  6. Step 6: Final answer
    x = 778.82

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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.