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Finding the Fourth Proportional to 721.85, 996.09 and 407.09

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Solution

The fourth proportional to 721.85, 996.09 and 407.09 is: 561.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.85 : 996.09 = 407.09 : x
  2. Step 2: Convert to fraction form
    721.85/996.09 = 407.09/x
  3. Step 3: Cross multiply
    721.85x = 996.09 × 407.09
  4. Step 4: Simplify right side
    721.85x = 405,493.30
  5. Step 5: Solve for x
    x = 405,493.30/721.85
  6. Step 6: Final answer
    x = 561.75

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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.