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Finding the Fourth Proportional to 780.62, 1,169.41 and 519.85

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Solution

The fourth proportional to 780.62, 1,169.41 and 519.85 is: 778.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.62 : 1,169.41 = 519.85 : x
  2. Step 2: Convert to fraction form
    780.62/1,169.41 = 519.85/x
  3. Step 3: Cross multiply
    780.62x = 1,169.41 × 519.85
  4. Step 4: Simplify right side
    780.62x = 607,913.57
  5. Step 5: Solve for x
    x = 607,913.57/780.62
  6. Step 6: Final answer
    x = 778.75

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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.