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Finding the Third Proportional to 8.15 and 20.90

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Solution

The third proportional to 8.15 and 20.90 is: 53.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    8.15 : 20.90 = 20.90 : x
  2. Step 2: Convert to fraction form
    8.15/20.90 = 20.90/x
  3. Step 3: Cross multiply
    8.15x = 20.90 × 20.90
  4. Step 4: Simplify right side
    8.15x = 436.68
  5. Step 5: Solve for x
    x = 436.68/8.15
  6. Step 6: Final answer
    x = 53.58

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Why These Related Problems?

These problems maintain the same ratio (2.56) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.