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Finding the Fourth Proportional to 629.40, 868.41 and 396.39

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Solution

The fourth proportional to 629.40, 868.41 and 396.39 is: 546.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    629.40 : 868.41 = 396.39 : x
  2. Step 2: Convert to fraction form
    629.40/868.41 = 396.39/x
  3. Step 3: Cross multiply
    629.40x = 868.41 × 396.39
  4. Step 4: Simplify right side
    629.40x = 344,229.04
  5. Step 5: Solve for x
    x = 344,229.04/629.40
  6. Step 6: Final answer
    x = 546.92

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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.