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Finding the Fourth Proportional to 644.90, 889.75 and 379.25

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Solution

The fourth proportional to 644.90, 889.75 and 379.25 is: 523.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    644.90 : 889.75 = 379.25 : x
  2. Step 2: Convert to fraction form
    644.90/889.75 = 379.25/x
  3. Step 3: Cross multiply
    644.90x = 889.75 × 379.25
  4. Step 4: Simplify right side
    644.90x = 337,440.39
  5. Step 5: Solve for x
    x = 337,440.39/644.90
  6. Step 6: Final answer
    x = 523.25

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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.