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Finding the Fourth Proportional to 513.72, 708.92 and 280.86

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Solution

The fourth proportional to 513.72, 708.92 and 280.86 is: 387.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    513.72 : 708.92 = 280.86 : x
  2. Step 2: Convert to fraction form
    513.72/708.92 = 280.86/x
  3. Step 3: Cross multiply
    513.72x = 708.92 × 280.86
  4. Step 4: Simplify right side
    513.72x = 199,107.27
  5. Step 5: Solve for x
    x = 199,107.27/513.72
  6. Step 6: Final answer
    x = 387.58

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.