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Finding the Fourth Proportional to 821.07, 1,229.92 and 403.99

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Solution

The fourth proportional to 821.07, 1,229.92 and 403.99 is: 605.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    821.07 : 1,229.92 = 403.99 : x
  2. Step 2: Convert to fraction form
    821.07/1,229.92 = 403.99/x
  3. Step 3: Cross multiply
    821.07x = 1,229.92 × 403.99
  4. Step 4: Simplify right side
    821.07x = 496,871.30
  5. Step 5: Solve for x
    x = 496,871.30/821.07
  6. Step 6: Final answer
    x = 605.15

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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.