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Finding the Fourth Proportional to 639.22, 882.09 and 403.12

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Solution

The fourth proportional to 639.22, 882.09 and 403.12 is: 556.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.22 : 882.09 = 403.12 : x
  2. Step 2: Convert to fraction form
    639.22/882.09 = 403.12/x
  3. Step 3: Cross multiply
    639.22x = 882.09 × 403.12
  4. Step 4: Simplify right side
    639.22x = 355,588.12
  5. Step 5: Solve for x
    x = 355,588.12/639.22
  6. Step 6: Final answer
    x = 556.28

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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.