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Finding the Fourth Proportional to 639.47, 882.09 and 415.30

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Solution

The fourth proportional to 639.47, 882.09 and 415.30 is: 572.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.47 : 882.09 = 415.30 : x
  2. Step 2: Convert to fraction form
    639.47/882.09 = 415.30/x
  3. Step 3: Cross multiply
    639.47x = 882.09 × 415.30
  4. Step 4: Simplify right side
    639.47x = 366,333.91
  5. Step 5: Solve for x
    x = 366,333.91/639.47
  6. Step 6: Final answer
    x = 572.87

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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.