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Finding the Fourth Proportional to 638.82, 882.90 and 509.22

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Solution

The fourth proportional to 638.82, 882.90 and 509.22 is: 703.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.82 : 882.90 = 509.22 : x
  2. Step 2: Convert to fraction form
    638.82/882.90 = 509.22/x
  3. Step 3: Cross multiply
    638.82x = 882.90 × 509.22
  4. Step 4: Simplify right side
    638.82x = 449,590.34
  5. Step 5: Solve for x
    x = 449,590.34/638.82
  6. Step 6: Final answer
    x = 703.78

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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.