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Finding the Fourth Proportional to 638.57, 881.39 and 376.67

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Solution

The fourth proportional to 638.57, 881.39 and 376.67 is: 519.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.57 : 881.39 = 376.67 : x
  2. Step 2: Convert to fraction form
    638.57/881.39 = 376.67/x
  3. Step 3: Cross multiply
    638.57x = 881.39 × 376.67
  4. Step 4: Simplify right side
    638.57x = 331,993.17
  5. Step 5: Solve for x
    x = 331,993.17/638.57
  6. Step 6: Final answer
    x = 519.90

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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.