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Finding the Fourth Proportional to 629.76, 869.15 and 381.09

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Solution

The fourth proportional to 629.76, 869.15 and 381.09 is: 525.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    629.76 : 869.15 = 381.09 : x
  2. Step 2: Convert to fraction form
    629.76/869.15 = 381.09/x
  3. Step 3: Cross multiply
    629.76x = 869.15 × 381.09
  4. Step 4: Simplify right side
    629.76x = 331,222.47
  5. Step 5: Solve for x
    x = 331,222.47/629.76
  6. Step 6: Final answer
    x = 525.95

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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.