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Finding the Fourth Proportional to 644.31, 966.83 and 639.09

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Solution

The fourth proportional to 644.31, 966.83 and 639.09 is: 959.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    644.31 : 966.83 = 639.09 : x
  2. Step 2: Convert to fraction form
    644.31/966.83 = 639.09/x
  3. Step 3: Cross multiply
    644.31x = 966.83 × 639.09
  4. Step 4: Simplify right side
    644.31x = 617,891.38
  5. Step 5: Solve for x
    x = 617,891.38/644.31
  6. Step 6: Final answer
    x = 959.00

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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.