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Finding the Fourth Proportional to 691.87, 954.39 and 397.09

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Solution

The fourth proportional to 691.87, 954.39 and 397.09 is: 547.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    691.87 : 954.39 = 397.09 : x
  2. Step 2: Convert to fraction form
    691.87/954.39 = 397.09/x
  3. Step 3: Cross multiply
    691.87x = 954.39 × 397.09
  4. Step 4: Simplify right side
    691.87x = 378,978.73
  5. Step 5: Solve for x
    x = 378,978.73/691.87
  6. Step 6: Final answer
    x = 547.76

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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.