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Finding the Fourth Proportional to 644.90, 890.39 and 495.27

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Solution

The fourth proportional to 644.90, 890.39 and 495.27 is: 683.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    644.90 : 890.39 = 495.27 : x
  2. Step 2: Convert to fraction form
    644.90/890.39 = 495.27/x
  3. Step 3: Cross multiply
    644.90x = 890.39 × 495.27
  4. Step 4: Simplify right side
    644.90x = 440,984.69
  5. Step 5: Solve for x
    x = 440,984.69/644.90
  6. Step 6: Final answer
    x = 683.81

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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.