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Finding the Fourth Proportional to 641.89, 885.45 and 442.70

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Solution

The fourth proportional to 641.89, 885.45 and 442.70 is: 610.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.89 : 885.45 = 442.70 : x
  2. Step 2: Convert to fraction form
    641.89/885.45 = 442.70/x
  3. Step 3: Cross multiply
    641.89x = 885.45 × 442.70
  4. Step 4: Simplify right side
    641.89x = 391,989.27
  5. Step 5: Solve for x
    x = 391,989.27/641.89
  6. Step 6: Final answer
    x = 610.68

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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.