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Finding the Fourth Proportional to 453.78, 680.72 and 129.20

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Solution

The fourth proportional to 453.78, 680.72 and 129.20 is: 193.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    453.78 : 680.72 = 129.20 : x
  2. Step 2: Convert to fraction form
    453.78/680.72 = 129.20/x
  3. Step 3: Cross multiply
    453.78x = 680.72 × 129.20
  4. Step 4: Simplify right side
    453.78x = 87,944.97
  5. Step 5: Solve for x
    x = 87,944.97/453.78
  6. Step 6: Final answer
    x = 193.81

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.