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Finding the Fourth Proportional to 426.21, 638.90 and 270.11

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Solution

The fourth proportional to 426.21, 638.90 and 270.11 is: 404.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.21 : 638.90 = 270.11 : x
  2. Step 2: Convert to fraction form
    426.21/638.90 = 270.11/x
  3. Step 3: Cross multiply
    426.21x = 638.90 × 270.11
  4. Step 4: Simplify right side
    426.21x = 172,573.28
  5. Step 5: Solve for x
    x = 172,573.28/426.21
  6. Step 6: Final answer
    x = 404.90

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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.