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Finding the Fourth Proportional to 639.20, 881.19 and 481.86

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Solution

The fourth proportional to 639.20, 881.19 and 481.86 is: 664.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.20 : 881.19 = 481.86 : x
  2. Step 2: Convert to fraction form
    639.20/881.19 = 481.86/x
  3. Step 3: Cross multiply
    639.20x = 881.19 × 481.86
  4. Step 4: Simplify right side
    639.20x = 424,610.21
  5. Step 5: Solve for x
    x = 424,610.21/639.20
  6. Step 6: Final answer
    x = 664.29

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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.