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Finding the Third Proportional to 3.81 and 8.09

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Solution

The third proportional to 3.81 and 8.09 is: 17.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    3.81 : 8.09 = 8.09 : x
  2. Step 2: Convert to fraction form
    3.81/8.09 = 8.09/x
  3. Step 3: Cross multiply
    3.81x = 8.09 × 8.09
  4. Step 4: Simplify right side
    3.81x = 65.51
  5. Step 5: Solve for x
    x = 65.51/3.81
  6. Step 6: Final answer
    x = 17.18

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Why These Related Problems?

These problems maintain the same ratio (2.12) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.