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Finding the Fourth Proportional to 638.20, 880.67 and 354.60

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Solution

The fourth proportional to 638.20, 880.67 and 354.60 is: 489.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.20 : 880.67 = 354.60 : x
  2. Step 2: Convert to fraction form
    638.20/880.67 = 354.60/x
  3. Step 3: Cross multiply
    638.20x = 880.67 × 354.60
  4. Step 4: Simplify right side
    638.20x = 312,285.58
  5. Step 5: Solve for x
    x = 312,285.58/638.20
  6. Step 6: Final answer
    x = 489.32

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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.