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Finding the Fourth Proportional to 644.90, 889.85 and 379.35

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Solution

The fourth proportional to 644.90, 889.85 and 379.35 is: 523.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    644.90 : 889.85 = 379.35 : x
  2. Step 2: Convert to fraction form
    644.90/889.85 = 379.35/x
  3. Step 3: Cross multiply
    644.90x = 889.85 × 379.35
  4. Step 4: Simplify right side
    644.90x = 337,565.55
  5. Step 5: Solve for x
    x = 337,565.55/644.90
  6. Step 6: Final answer
    x = 523.44

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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.