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Finding the Fourth Proportional to 426.20, 638.82 and 289.28

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Solution

The fourth proportional to 426.20, 638.82 and 289.28 is: 433.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.20 : 638.82 = 289.28 : x
  2. Step 2: Convert to fraction form
    426.20/638.82 = 289.28/x
  3. Step 3: Cross multiply
    426.20x = 638.82 × 289.28
  4. Step 4: Simplify right side
    426.20x = 184,797.85
  5. Step 5: Solve for x
    x = 184,797.85/426.20
  6. Step 6: Final answer
    x = 433.59

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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.