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Finding the Fourth Proportional to 871.26, 1,306.86 and 408.87

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Solution

The fourth proportional to 871.26, 1,306.86 and 408.87 is: 613.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    871.26 : 1,306.86 = 408.87 : x
  2. Step 2: Convert to fraction form
    871.26/1,306.86 = 408.87/x
  3. Step 3: Cross multiply
    871.26x = 1,306.86 × 408.87
  4. Step 4: Simplify right side
    871.26x = 534,335.85
  5. Step 5: Solve for x
    x = 534,335.85/871.26
  6. Step 6: Final answer
    x = 613.29

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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.