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Finding the Fourth Proportional to 640.20, 882.90 and 404.16

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Solution

The fourth proportional to 640.20, 882.90 and 404.16 is: 557.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.20 : 882.90 = 404.16 : x
  2. Step 2: Convert to fraction form
    640.20/882.90 = 404.16/x
  3. Step 3: Cross multiply
    640.20x = 882.90 × 404.16
  4. Step 4: Simplify right side
    640.20x = 356,832.86
  5. Step 5: Solve for x
    x = 356,832.86/640.20
  6. Step 6: Final answer
    x = 557.38

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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.