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Finding the Fourth Proportional to 871.10, 1,306.59 and 408.99

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Solution

The fourth proportional to 871.10, 1,306.59 and 408.99 is: 613.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    871.10 : 1,306.59 = 408.99 : x
  2. Step 2: Convert to fraction form
    871.10/1,306.59 = 408.99/x
  3. Step 3: Cross multiply
    871.10x = 1,306.59 × 408.99
  4. Step 4: Simplify right side
    871.10x = 534,377.34
  5. Step 5: Solve for x
    x = 534,377.34/871.10
  6. Step 6: Final answer
    x = 613.45

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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.