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Finding the Fourth Proportional to 638.92, 880.38 and 498.82

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Solution

The fourth proportional to 638.92, 880.38 and 498.82 is: 687.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.92 : 880.38 = 498.82 : x
  2. Step 2: Convert to fraction form
    638.92/880.38 = 498.82/x
  3. Step 3: Cross multiply
    638.92x = 880.38 × 498.82
  4. Step 4: Simplify right side
    638.92x = 439,151.15
  5. Step 5: Solve for x
    x = 439,151.15/638.92
  6. Step 6: Final answer
    x = 687.33

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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.