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Finding the Fourth Proportional to 639.20, 882.11 and 377.21

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Solution

The fourth proportional to 639.20, 882.11 and 377.21 is: 520.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.20 : 882.11 = 377.21 : x
  2. Step 2: Convert to fraction form
    639.20/882.11 = 377.21/x
  3. Step 3: Cross multiply
    639.20x = 882.11 × 377.21
  4. Step 4: Simplify right side
    639.20x = 332,734.42
  5. Step 5: Solve for x
    x = 332,734.42/639.20
  6. Step 6: Final answer
    x = 520.55

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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.