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Finding the Fourth Proportional to 629.74, 868.81 and 380.88

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Solution

The fourth proportional to 629.74, 868.81 and 380.88 is: 525.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    629.74 : 868.81 = 380.88 : x
  2. Step 2: Convert to fraction form
    629.74/868.81 = 380.88/x
  3. Step 3: Cross multiply
    629.74x = 868.81 × 380.88
  4. Step 4: Simplify right side
    629.74x = 330,912.35
  5. Step 5: Solve for x
    x = 330,912.35/629.74
  6. Step 6: Final answer
    x = 525.47

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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.