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Finding the Fourth Proportional to 518.90, 778.43 and 258.92

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Solution

The fourth proportional to 518.90, 778.43 and 258.92 is: 388.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.90 : 778.43 = 258.92 : x
  2. Step 2: Convert to fraction form
    518.90/778.43 = 258.92/x
  3. Step 3: Cross multiply
    518.90x = 778.43 × 258.92
  4. Step 4: Simplify right side
    518.90x = 201,545.91
  5. Step 5: Solve for x
    x = 201,545.91/518.90
  6. Step 6: Final answer
    x = 388.41

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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.