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Finding the Fourth Proportional to 638.51, 881.39 and 481.60

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Solution

The fourth proportional to 638.51, 881.39 and 481.60 is: 664.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.51 : 881.39 = 481.60 : x
  2. Step 2: Convert to fraction form
    638.51/881.39 = 481.60/x
  3. Step 3: Cross multiply
    638.51x = 881.39 × 481.60
  4. Step 4: Simplify right side
    638.51x = 424,470.61
  5. Step 5: Solve for x
    x = 424,470.61/638.51
  6. Step 6: Final answer
    x = 664.78

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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.