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Finding the Fourth Proportional to 629.39, 868.59 and 405.09

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Solution

The fourth proportional to 629.39, 868.59 and 405.09 is: 559.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    629.39 : 868.59 = 405.09 : x
  2. Step 2: Convert to fraction form
    629.39/868.59 = 405.09/x
  3. Step 3: Cross multiply
    629.39x = 868.59 × 405.09
  4. Step 4: Simplify right side
    629.39x = 351,857.12
  5. Step 5: Solve for x
    x = 351,857.12/629.39
  6. Step 6: Final answer
    x = 559.04

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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.