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Finding the Fourth Proportional to 642.20, 884.72 and 445.37

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Solution

The fourth proportional to 642.20, 884.72 and 445.37 is: 613.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.20 : 884.72 = 445.37 : x
  2. Step 2: Convert to fraction form
    642.20/884.72 = 445.37/x
  3. Step 3: Cross multiply
    642.20x = 884.72 × 445.37
  4. Step 4: Simplify right side
    642.20x = 394,024.44
  5. Step 5: Solve for x
    x = 394,024.44/642.20
  6. Step 6: Final answer
    x = 613.56

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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.