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Finding the Fourth Proportional to 629.72, 868.84 and 408.39

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Solution

The fourth proportional to 629.72, 868.84 and 408.39 is: 563.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    629.72 : 868.84 = 408.39 : x
  2. Step 2: Convert to fraction form
    629.72/868.84 = 408.39/x
  3. Step 3: Cross multiply
    629.72x = 868.84 × 408.39
  4. Step 4: Simplify right side
    629.72x = 354,825.57
  5. Step 5: Solve for x
    x = 354,825.57/629.72
  6. Step 6: Final answer
    x = 563.47

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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.