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Finding the Third Proportional to 3.80 and 7.81

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Solution

The third proportional to 3.80 and 7.81 is: 16.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    3.80 : 7.81 = 7.81 : x
  2. Step 2: Convert to fraction form
    3.80/7.81 = 7.81/x
  3. Step 3: Cross multiply
    3.80x = 7.81 × 7.81
  4. Step 4: Simplify right side
    3.80x = 60.98
  5. Step 5: Solve for x
    x = 60.98/3.80
  6. Step 6: Final answer
    x = 16.03

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Why These Related Problems?

These problems maintain the same ratio (2.05) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.