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Finding the Fourth Proportional to 644.21, 889.09 and 447.38

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Solution

The fourth proportional to 644.21, 889.09 and 447.38 is: 617.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    644.21 : 889.09 = 447.38 : x
  2. Step 2: Convert to fraction form
    644.21/889.09 = 447.38/x
  3. Step 3: Cross multiply
    644.21x = 889.09 × 447.38
  4. Step 4: Simplify right side
    644.21x = 397,761.08
  5. Step 5: Solve for x
    x = 397,761.08/644.21
  6. Step 6: Final answer
    x = 617.44

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.