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Finding the Fourth Proportional to 640.54, 883.96 and 378.56

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Solution

The fourth proportional to 640.54, 883.96 and 378.56 is: 522.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.54 : 883.96 = 378.56 : x
  2. Step 2: Convert to fraction form
    640.54/883.96 = 378.56/x
  3. Step 3: Cross multiply
    640.54x = 883.96 × 378.56
  4. Step 4: Simplify right side
    640.54x = 334,631.90
  5. Step 5: Solve for x
    x = 334,631.90/640.54
  6. Step 6: Final answer
    x = 522.42

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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.