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Finding the Fourth Proportional to 638.76, 882.63 and 499.23

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Solution

The fourth proportional to 638.76, 882.63 and 499.23 is: 689.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.76 : 882.63 = 499.23 : x
  2. Step 2: Convert to fraction form
    638.76/882.63 = 499.23/x
  3. Step 3: Cross multiply
    638.76x = 882.63 × 499.23
  4. Step 4: Simplify right side
    638.76x = 440,635.37
  5. Step 5: Solve for x
    x = 440,635.37/638.76
  6. Step 6: Final answer
    x = 689.83

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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.