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Finding the Fourth Proportional to 426.39, 639.17 and 271.88

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Solution

The fourth proportional to 426.39, 639.17 and 271.88 is: 407.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.39 : 639.17 = 271.88 : x
  2. Step 2: Convert to fraction form
    426.39/639.17 = 271.88/x
  3. Step 3: Cross multiply
    426.39x = 639.17 × 271.88
  4. Step 4: Simplify right side
    426.39x = 173,777.54
  5. Step 5: Solve for x
    x = 173,777.54/426.39
  6. Step 6: Final answer
    x = 407.56

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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.