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Finding the Fourth Proportional to 639.73, 882.67 and 391.03

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Solution

The fourth proportional to 639.73, 882.67 and 391.03 is: 539.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.73 : 882.67 = 391.03 : x
  2. Step 2: Convert to fraction form
    639.73/882.67 = 391.03/x
  3. Step 3: Cross multiply
    639.73x = 882.67 × 391.03
  4. Step 4: Simplify right side
    639.73x = 345,150.45
  5. Step 5: Solve for x
    x = 345,150.45/639.73
  6. Step 6: Final answer
    x = 539.53

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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.