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Finding the Fourth Proportional to 638.10, 880.57 and 354.50

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Solution

The fourth proportional to 638.10, 880.57 and 354.50 is: 489.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.10 : 880.57 = 354.50 : x
  2. Step 2: Convert to fraction form
    638.10/880.57 = 354.50/x
  3. Step 3: Cross multiply
    638.10x = 880.57 × 354.50
  4. Step 4: Simplify right side
    638.10x = 312,163.38
  5. Step 5: Solve for x
    x = 312,163.38/638.10
  6. Step 6: Final answer
    x = 489.21

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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.