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Finding the Fourth Proportional to 519.31, 778.71 and 259.40

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Solution

The fourth proportional to 519.31, 778.71 and 259.40 is: 388.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    519.31 : 778.71 = 259.40 : x
  2. Step 2: Convert to fraction form
    519.31/778.71 = 259.40/x
  3. Step 3: Cross multiply
    519.31x = 778.71 × 259.40
  4. Step 4: Simplify right side
    519.31x = 202,000.29
  5. Step 5: Solve for x
    x = 202,000.29/519.31
  6. Step 6: Final answer
    x = 388.98

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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.