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Finding the Fourth Proportional to 640.57, 961.03 and 207.85

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Solution

The fourth proportional to 640.57, 961.03 and 207.85 is: 311.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.57 : 961.03 = 207.85 : x
  2. Step 2: Convert to fraction form
    640.57/961.03 = 207.85/x
  3. Step 3: Cross multiply
    640.57x = 961.03 × 207.85
  4. Step 4: Simplify right side
    640.57x = 199,750.09
  5. Step 5: Solve for x
    x = 199,750.09/640.57
  6. Step 6: Final answer
    x = 311.83

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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.