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Finding the Fourth Proportional to 426.08, 638.28 and 220.40

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Solution

The fourth proportional to 426.08, 638.28 and 220.40 is: 330.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.08 : 638.28 = 220.40 : x
  2. Step 2: Convert to fraction form
    426.08/638.28 = 220.40/x
  3. Step 3: Cross multiply
    426.08x = 638.28 × 220.40
  4. Step 4: Simplify right side
    426.08x = 140,676.91
  5. Step 5: Solve for x
    x = 140,676.91/426.08
  6. Step 6: Final answer
    x = 330.17

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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.