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Finding the Fourth Proportional to 640.70, 961.20 and 229.88

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Solution

The fourth proportional to 640.70, 961.20 and 229.88 is: 344.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.70 : 961.20 = 229.88 : x
  2. Step 2: Convert to fraction form
    640.70/961.20 = 229.88/x
  3. Step 3: Cross multiply
    640.70x = 961.20 × 229.88
  4. Step 4: Simplify right side
    640.70x = 220,960.66
  5. Step 5: Solve for x
    x = 220,960.66/640.70
  6. Step 6: Final answer
    x = 344.87

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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.