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Finding the Third Proportional to 9 and 27

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Solution

The third proportional to 9 and 27 is: 81

Step by Step Solution

  1. Step 1: Write the proportion equation
    9 : 27 = 27 : x
  2. Step 2: Convert to fraction form
    9/27 = 27/x
  3. Step 3: Cross multiply
    9x = 27 × 27
  4. Step 4: Simplify right side
    9x = 729
  5. Step 5: Solve for x
    x = 729/9
  6. Step 6: Final answer
    x = 81

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Why These Related Problems?

These problems maintain the same ratio (3) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.