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Finding the Fourth Proportional to 638.82, 881.58 and 499.10

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Solution

The fourth proportional to 638.82, 881.58 and 499.10 is: 688.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.82 : 881.58 = 499.10 : x
  2. Step 2: Convert to fraction form
    638.82/881.58 = 499.10/x
  3. Step 3: Cross multiply
    638.82x = 881.58 × 499.10
  4. Step 4: Simplify right side
    638.82x = 439,990.92
  5. Step 5: Solve for x
    x = 439,990.92/638.82
  6. Step 6: Final answer
    x = 688.76

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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.