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Finding the Fourth Proportional to 640.20, 883.46 and 378.28

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Solution

The fourth proportional to 640.20, 883.46 and 378.28 is: 522.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.20 : 883.46 = 378.28 : x
  2. Step 2: Convert to fraction form
    640.20/883.46 = 378.28/x
  3. Step 3: Cross multiply
    640.20x = 883.46 × 378.28
  4. Step 4: Simplify right side
    640.20x = 334,195.25
  5. Step 5: Solve for x
    x = 334,195.25/640.20
  6. Step 6: Final answer
    x = 522.02

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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.