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Finding the Fourth Proportional to 638.17, 880.62 and 428.31

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Solution

The fourth proportional to 638.17, 880.62 and 428.31 is: 591.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.17 : 880.62 = 428.31 : x
  2. Step 2: Convert to fraction form
    638.17/880.62 = 428.31/x
  3. Step 3: Cross multiply
    638.17x = 880.62 × 428.31
  4. Step 4: Simplify right side
    638.17x = 377,176.75
  5. Step 5: Solve for x
    x = 377,176.75/638.17
  6. Step 6: Final answer
    x = 591.03

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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.