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Finding the Third Proportional to 81 and 171

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Solution

The third proportional to 81 and 171 is: 361

Step by Step Solution

  1. Step 1: Write the proportion equation
    81 : 171 = 171 : x
  2. Step 2: Convert to fraction form
    81/171 = 171/x
  3. Step 3: Cross multiply
    81x = 171 × 171
  4. Step 4: Simplify right side
    81x = 29,241
  5. Step 5: Solve for x
    x = 29,241/81
  6. Step 6: Final answer
    x = 361

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Why These Related Problems?

These problems maintain the same ratio (2.11) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.