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Finding the Fourth Proportional to 640.98, 884.43 and 378.90

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Solution

The fourth proportional to 640.98, 884.43 and 378.90 is: 522.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.98 : 884.43 = 378.90 : x
  2. Step 2: Convert to fraction form
    640.98/884.43 = 378.90/x
  3. Step 3: Cross multiply
    640.98x = 884.43 × 378.90
  4. Step 4: Simplify right side
    640.98x = 335,110.53
  5. Step 5: Solve for x
    x = 335,110.53/640.98
  6. Step 6: Final answer
    x = 522.81

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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.