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Finding the Fourth Proportional to 519.78, 717.29 and 286.90

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Solution

The fourth proportional to 519.78, 717.29 and 286.90 is: 395.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    519.78 : 717.29 = 286.90 : x
  2. Step 2: Convert to fraction form
    519.78/717.29 = 286.90/x
  3. Step 3: Cross multiply
    519.78x = 717.29 × 286.90
  4. Step 4: Simplify right side
    519.78x = 205,789.07
  5. Step 5: Solve for x
    x = 205,789.07/519.78
  6. Step 6: Final answer
    x = 395.92

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.