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Finding the Fourth Proportional to 641.20, 884.94 and 392.57

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Solution

The fourth proportional to 641.20, 884.94 and 392.57 is: 541.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.20 : 884.94 = 392.57 : x
  2. Step 2: Convert to fraction form
    641.20/884.94 = 392.57/x
  3. Step 3: Cross multiply
    641.20x = 884.94 × 392.57
  4. Step 4: Simplify right side
    641.20x = 347,400.90
  5. Step 5: Solve for x
    x = 347,400.90/641.20
  6. Step 6: Final answer
    x = 541.80

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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.