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Finding the Third Proportional to 81 and 135

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Solution

The third proportional to 81 and 135 is: 225

Step by Step Solution

  1. Step 1: Write the proportion equation
    81 : 135 = 135 : x
  2. Step 2: Convert to fraction form
    81/135 = 135/x
  3. Step 3: Cross multiply
    81x = 135 × 135
  4. Step 4: Simplify right side
    81x = 18,225
  5. Step 5: Solve for x
    x = 18,225/81
  6. Step 6: Final answer
    x = 225

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Why These Related Problems?

These problems maintain the same ratio (1.67) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.