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Finding the Fourth Proportional to 513.70, 708.91 and 280.83

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Solution

The fourth proportional to 513.70, 708.91 and 280.83 is: 387.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    513.70 : 708.91 = 280.83 : x
  2. Step 2: Convert to fraction form
    513.70/708.91 = 280.83/x
  3. Step 3: Cross multiply
    513.70x = 708.91 × 280.83
  4. Step 4: Simplify right side
    513.70x = 199,081.95
  5. Step 5: Solve for x
    x = 199,081.95/513.70
  6. Step 6: Final answer
    x = 387.54

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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.