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Finding the Fourth Proportional to 638.62, 958.84 and 394.40

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Solution

The fourth proportional to 638.62, 958.84 and 394.40 is: 592.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.62 : 958.84 = 394.40 : x
  2. Step 2: Convert to fraction form
    638.62/958.84 = 394.40/x
  3. Step 3: Cross multiply
    638.62x = 958.84 × 394.40
  4. Step 4: Simplify right side
    638.62x = 378,167.91
  5. Step 5: Solve for x
    x = 378,167.91/638.62
  6. Step 6: Final answer
    x = 592.17

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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.