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Finding the Fourth Proportional to 387.31, 579.83 and 255.68

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Solution

The fourth proportional to 387.31, 579.83 and 255.68 is: 382.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.31 : 579.83 = 255.68 : x
  2. Step 2: Convert to fraction form
    387.31/579.83 = 255.68/x
  3. Step 3: Cross multiply
    387.31x = 579.83 × 255.68
  4. Step 4: Simplify right side
    387.31x = 148,252.72
  5. Step 5: Solve for x
    x = 148,252.72/387.31
  6. Step 6: Final answer
    x = 382.78

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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.