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Finding the Fourth Proportional to 871.41, 1,306.87 and 408.95

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Solution

The fourth proportional to 871.41, 1,306.87 and 408.95 is: 613.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    871.41 : 1,306.87 = 408.95 : x
  2. Step 2: Convert to fraction form
    871.41/1,306.87 = 408.95/x
  3. Step 3: Cross multiply
    871.41x = 1,306.87 × 408.95
  4. Step 4: Simplify right side
    871.41x = 534,444.49
  5. Step 5: Solve for x
    x = 534,444.49/871.41
  6. Step 6: Final answer
    x = 613.31

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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.