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Finding the Fourth Proportional to 638.31, 956.43 and 329.70

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Solution

The fourth proportional to 638.31, 956.43 and 329.70 is: 494.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.31 : 956.43 = 329.70 : x
  2. Step 2: Convert to fraction form
    638.31/956.43 = 329.70/x
  3. Step 3: Cross multiply
    638.31x = 956.43 × 329.70
  4. Step 4: Simplify right side
    638.31x = 315,334.97
  5. Step 5: Solve for x
    x = 315,334.97/638.31
  6. Step 6: Final answer
    x = 494.02

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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.