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Finding the Fourth Proportional to 640.05, 882.45 and 490.84

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Solution

The fourth proportional to 640.05, 882.45 and 490.84 is: 676.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.05 : 882.45 = 490.84 : x
  2. Step 2: Convert to fraction form
    640.05/882.45 = 490.84/x
  3. Step 3: Cross multiply
    640.05x = 882.45 × 490.84
  4. Step 4: Simplify right side
    640.05x = 433,141.76
  5. Step 5: Solve for x
    x = 433,141.76/640.05
  6. Step 6: Final answer
    x = 676.73

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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.