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Finding the Fourth Proportional to 691.50, 954.30 and 396.72

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Solution

The fourth proportional to 691.50, 954.30 and 396.72 is: 547.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    691.50 : 954.30 = 396.72 : x
  2. Step 2: Convert to fraction form
    691.50/954.30 = 396.72/x
  3. Step 3: Cross multiply
    691.50x = 954.30 × 396.72
  4. Step 4: Simplify right side
    691.50x = 378,589.90
  5. Step 5: Solve for x
    x = 378,589.90/691.50
  6. Step 6: Final answer
    x = 547.49

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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.