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Finding the Fourth Proportional to 54.15, 81.24 and 18.09

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Solution

The fourth proportional to 54.15, 81.24 and 18.09 is: 27.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    54.15 : 81.24 = 18.09 : x
  2. Step 2: Convert to fraction form
    54.15/81.24 = 18.09/x
  3. Step 3: Cross multiply
    54.15x = 81.24 × 18.09
  4. Step 4: Simplify right side
    54.15x = 1,469.13
  5. Step 5: Solve for x
    x = 1,469.13/54.15
  6. Step 6: Final answer
    x = 27.13

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.