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Finding the Fourth Proportional to 629.37, 868.47 and 380.78

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Solution

The fourth proportional to 629.37, 868.47 and 380.78 is: 525.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    629.37 : 868.47 = 380.78 : x
  2. Step 2: Convert to fraction form
    629.37/868.47 = 380.78/x
  3. Step 3: Cross multiply
    629.37x = 868.47 × 380.78
  4. Step 4: Simplify right side
    629.37x = 330,691.66
  5. Step 5: Solve for x
    x = 330,691.66/629.37
  6. Step 6: Final answer
    x = 525.43

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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.