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Finding the Fourth Proportional to 638.30, 880.82 and 358.54

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Solution

The fourth proportional to 638.30, 880.82 and 358.54 is: 494.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.30 : 880.82 = 358.54 : x
  2. Step 2: Convert to fraction form
    638.30/880.82 = 358.54/x
  3. Step 3: Cross multiply
    638.30x = 880.82 × 358.54
  4. Step 4: Simplify right side
    638.30x = 315,813.52
  5. Step 5: Solve for x
    x = 315,813.52/638.30
  6. Step 6: Final answer
    x = 494.78

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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.