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Finding the Fourth Proportional to 518.60, 778.41 and 287.75

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Solution

The fourth proportional to 518.60, 778.41 and 287.75 is: 431.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.60 : 778.41 = 287.75 : x
  2. Step 2: Convert to fraction form
    518.60/778.41 = 287.75/x
  3. Step 3: Cross multiply
    518.60x = 778.41 × 287.75
  4. Step 4: Simplify right side
    518.60x = 223,989.42
  5. Step 5: Solve for x
    x = 223,989.42/518.60
  6. Step 6: Final answer
    x = 431.91

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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.