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Finding the Fourth Proportional to 722.68, 997.29 and 391.11

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Solution

The fourth proportional to 722.68, 997.29 and 391.11 is: 539.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    722.68 : 997.29 = 391.11 : x
  2. Step 2: Convert to fraction form
    722.68/997.29 = 391.11/x
  3. Step 3: Cross multiply
    722.68x = 997.29 × 391.11
  4. Step 4: Simplify right side
    722.68x = 390,046.35
  5. Step 5: Solve for x
    x = 390,046.35/722.68
  6. Step 6: Final answer
    x = 539.72

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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.