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Finding the Fourth Proportional to 439.20, 656.91 and 427.41

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Solution

The fourth proportional to 439.20, 656.91 and 427.41 is: 639.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    439.20 : 656.91 = 427.41 : x
  2. Step 2: Convert to fraction form
    439.20/656.91 = 427.41/x
  3. Step 3: Cross multiply
    439.20x = 656.91 × 427.41
  4. Step 4: Simplify right side
    439.20x = 280,769.90
  5. Step 5: Solve for x
    x = 280,769.90/439.20
  6. Step 6: Final answer
    x = 639.28

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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.