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Finding the Fourth Proportional to 440.20, 658.41 and 428.41

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Solution

The fourth proportional to 440.20, 658.41 and 428.41 is: 640.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    440.20 : 658.41 = 428.41 : x
  2. Step 2: Convert to fraction form
    440.20/658.41 = 428.41/x
  3. Step 3: Cross multiply
    440.20x = 658.41 × 428.41
  4. Step 4: Simplify right side
    440.20x = 282,069.43
  5. Step 5: Solve for x
    x = 282,069.43/440.20
  6. Step 6: Final answer
    x = 640.78

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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.