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Finding the Fourth Proportional to 639.43, 958.38 and 331.42

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Solution

The fourth proportional to 639.43, 958.38 and 331.42 is: 496.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.43 : 958.38 = 331.42 : x
  2. Step 2: Convert to fraction form
    639.43/958.38 = 331.42/x
  3. Step 3: Cross multiply
    639.43x = 958.38 × 331.42
  4. Step 4: Simplify right side
    639.43x = 317,626.30
  5. Step 5: Solve for x
    x = 317,626.30/639.43
  6. Step 6: Final answer
    x = 496.73

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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.