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Finding the Fourth Proportional to 83.11, 115.02 and 81.09

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Solution

The fourth proportional to 83.11, 115.02 and 81.09 is: 112.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    83.11 : 115.02 = 81.09 : x
  2. Step 2: Convert to fraction form
    83.11/115.02 = 81.09/x
  3. Step 3: Cross multiply
    83.11x = 115.02 × 81.09
  4. Step 4: Simplify right side
    83.11x = 9,326.40
  5. Step 5: Solve for x
    x = 9,326.40/83.11
  6. Step 6: Final answer
    x = 112.22

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.