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Finding the Fourth Proportional to 428.20, 641.94 and 168.06

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Solution

The fourth proportional to 428.20, 641.94 and 168.06 is: 251.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.20 : 641.94 = 168.06 : x
  2. Step 2: Convert to fraction form
    428.20/641.94 = 168.06/x
  3. Step 3: Cross multiply
    428.20x = 641.94 × 168.06
  4. Step 4: Simplify right side
    428.20x = 107,884.44
  5. Step 5: Solve for x
    x = 107,884.44/428.20
  6. Step 6: Final answer
    x = 251.95

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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.