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Finding the Fourth Proportional to 722.78, 997.29 and 428.09

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Solution

The fourth proportional to 722.78, 997.29 and 428.09 is: 590.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    722.78 : 997.29 = 428.09 : x
  2. Step 2: Convert to fraction form
    722.78/997.29 = 428.09/x
  3. Step 3: Cross multiply
    722.78x = 997.29 × 428.09
  4. Step 4: Simplify right side
    722.78x = 426,929.88
  5. Step 5: Solve for x
    x = 426,929.88/722.78
  6. Step 6: Final answer
    x = 590.68

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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.