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Finding the Fourth Proportional to 639.29, 882.26 and 355.72

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Solution

The fourth proportional to 639.29, 882.26 and 355.72 is: 490.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.29 : 882.26 = 355.72 : x
  2. Step 2: Convert to fraction form
    639.29/882.26 = 355.72/x
  3. Step 3: Cross multiply
    639.29x = 882.26 × 355.72
  4. Step 4: Simplify right side
    639.29x = 313,837.53
  5. Step 5: Solve for x
    x = 313,837.53/639.29
  6. Step 6: Final answer
    x = 490.92

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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.