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Finding the Fourth Proportional to 644.30, 889.23 and 545.90

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Solution

The fourth proportional to 644.30, 889.23 and 545.90 is: 753.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    644.30 : 889.23 = 545.90 : x
  2. Step 2: Convert to fraction form
    644.30/889.23 = 545.90/x
  3. Step 3: Cross multiply
    644.30x = 889.23 × 545.90
  4. Step 4: Simplify right side
    644.30x = 485,430.66
  5. Step 5: Solve for x
    x = 485,430.66/644.30
  6. Step 6: Final answer
    x = 753.42

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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.