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Finding the Fourth Proportional to 638.87, 881.37 and 376.76

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Solution

The fourth proportional to 638.87, 881.37 and 376.76 is: 519.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.87 : 881.37 = 376.76 : x
  2. Step 2: Convert to fraction form
    638.87/881.37 = 376.76/x
  3. Step 3: Cross multiply
    638.87x = 881.37 × 376.76
  4. Step 4: Simplify right side
    638.87x = 332,064.96
  5. Step 5: Solve for x
    x = 332,064.96/638.87
  6. Step 6: Final answer
    x = 519.77

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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.