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Finding the Fourth Proportional to 640.66, 884.14 and 378.82

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Solution

The fourth proportional to 640.66, 884.14 and 378.82 is: 522.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.66 : 884.14 = 378.82 : x
  2. Step 2: Convert to fraction form
    640.66/884.14 = 378.82/x
  3. Step 3: Cross multiply
    640.66x = 884.14 × 378.82
  4. Step 4: Simplify right side
    640.66x = 334,929.91
  5. Step 5: Solve for x
    x = 334,929.91/640.66
  6. Step 6: Final answer
    x = 522.79

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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.