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Finding the Fourth Proportional to 638.38, 880.86 and 376.42

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Solution

The fourth proportional to 638.38, 880.86 and 376.42 is: 519.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.38 : 880.86 = 376.42 : x
  2. Step 2: Convert to fraction form
    638.38/880.86 = 376.42/x
  3. Step 3: Cross multiply
    638.38x = 880.86 × 376.42
  4. Step 4: Simplify right side
    638.38x = 331,573.32
  5. Step 5: Solve for x
    x = 331,573.32/638.38
  6. Step 6: Final answer
    x = 519.40

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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.