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Finding the Fourth Proportional to 638.92, 881.74 and 355.34

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Solution

The fourth proportional to 638.92, 881.74 and 355.34 is: 490.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.92 : 881.74 = 355.34 : x
  2. Step 2: Convert to fraction form
    638.92/881.74 = 355.34/x
  3. Step 3: Cross multiply
    638.92x = 881.74 × 355.34
  4. Step 4: Simplify right side
    638.92x = 313,317.49
  5. Step 5: Solve for x
    x = 313,317.49/638.92
  6. Step 6: Final answer
    x = 490.39

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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.