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Finding the Fourth Proportional to 644.40, 889.34 and 395.73

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Solution

The fourth proportional to 644.40, 889.34 and 395.73 is: 546.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    644.40 : 889.34 = 395.73 : x
  2. Step 2: Convert to fraction form
    644.40/889.34 = 395.73/x
  3. Step 3: Cross multiply
    644.40x = 889.34 × 395.73
  4. Step 4: Simplify right side
    644.40x = 351,936.54
  5. Step 5: Solve for x
    x = 351,936.54/644.40
  6. Step 6: Final answer
    x = 546.15

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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.