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Finding the Fourth Proportional to 640.70, 884.05 and 378.70

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Solution

The fourth proportional to 640.70, 884.05 and 378.70 is: 522.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.70 : 884.05 = 378.70 : x
  2. Step 2: Convert to fraction form
    640.70/884.05 = 378.70/x
  3. Step 3: Cross multiply
    640.70x = 884.05 × 378.70
  4. Step 4: Simplify right side
    640.70x = 334,789.74
  5. Step 5: Solve for x
    x = 334,789.74/640.70
  6. Step 6: Final answer
    x = 522.54

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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.