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Finding the Fourth Proportional to 640.29, 960.45 and 207.39

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Solution

The fourth proportional to 640.29, 960.45 and 207.39 is: 311.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.29 : 960.45 = 207.39 : x
  2. Step 2: Convert to fraction form
    640.29/960.45 = 207.39/x
  3. Step 3: Cross multiply
    640.29x = 960.45 × 207.39
  4. Step 4: Simplify right side
    640.29x = 199,187.73
  5. Step 5: Solve for x
    x = 199,187.73/640.29
  6. Step 6: Final answer
    x = 311.09

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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.