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Finding the Fourth Proportional to 518.58, 778.11 and 258.57

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Solution

The fourth proportional to 518.58, 778.11 and 258.57 is: 387.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.58 : 778.11 = 258.57 : x
  2. Step 2: Convert to fraction form
    518.58/778.11 = 258.57/x
  3. Step 3: Cross multiply
    518.58x = 778.11 × 258.57
  4. Step 4: Simplify right side
    518.58x = 201,195.90
  5. Step 5: Solve for x
    x = 201,195.90/518.58
  6. Step 6: Final answer
    x = 387.97

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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.