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Finding the Third Proportional to 20.72 and 40.92

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Solution

The third proportional to 20.72 and 40.92 is: 80.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.72 : 40.92 = 40.92 : x
  2. Step 2: Convert to fraction form
    20.72/40.92 = 40.92/x
  3. Step 3: Cross multiply
    20.72x = 40.92 × 40.92
  4. Step 4: Simplify right side
    20.72x = 1,674.60
  5. Step 5: Solve for x
    x = 1,674.60/20.72
  6. Step 6: Final answer
    x = 80.83

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Why These Related Problems?

These problems maintain the same ratio (1.98) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.