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Finding the Third Proportional to 3.87 and 8.51

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Solution

The third proportional to 3.87 and 8.51 is: 18.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    3.87 : 8.51 = 8.51 : x
  2. Step 2: Convert to fraction form
    3.87/8.51 = 8.51/x
  3. Step 3: Cross multiply
    3.87x = 8.51 × 8.51
  4. Step 4: Simplify right side
    3.87x = 72.38
  5. Step 5: Solve for x
    x = 72.38/3.87
  6. Step 6: Final answer
    x = 18.72

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Why These Related Problems?

These problems maintain the same ratio (2.20) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.