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Finding the Fourth Proportional to 627.40, 939.36 and 408.28

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Solution

The fourth proportional to 627.40, 939.36 and 408.28 is: 611.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    627.40 : 939.36 = 408.28 : x
  2. Step 2: Convert to fraction form
    627.40/939.36 = 408.28/x
  3. Step 3: Cross multiply
    627.40x = 939.36 × 408.28
  4. Step 4: Simplify right side
    627.40x = 383,522.84
  5. Step 5: Solve for x
    x = 383,522.84/627.40
  6. Step 6: Final answer
    x = 611.29

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.