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Finding the Fourth Proportional to 644.90, 967.19 and 439.40

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Solution

The fourth proportional to 644.90, 967.19 and 439.40 is: 658.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    644.90 : 967.19 = 439.40 : x
  2. Step 2: Convert to fraction form
    644.90/967.19 = 439.40/x
  3. Step 3: Cross multiply
    644.90x = 967.19 × 439.40
  4. Step 4: Simplify right side
    644.90x = 424,976.25
  5. Step 5: Solve for x
    x = 424,976.25/644.90
  6. Step 6: Final answer
    x = 658.99

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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.