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Finding the Fourth Proportional to 639.25, 882.17 and 418.57

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Solution

The fourth proportional to 639.25, 882.17 and 418.57 is: 577.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.25 : 882.17 = 418.57 : x
  2. Step 2: Convert to fraction form
    639.25/882.17 = 418.57/x
  3. Step 3: Cross multiply
    639.25x = 882.17 × 418.57
  4. Step 4: Simplify right side
    639.25x = 369,249.90
  5. Step 5: Solve for x
    x = 369,249.90/639.25
  6. Step 6: Final answer
    x = 577.63

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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.