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Finding the Fourth Proportional to 87.11, 120.17 and 57.66

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Solution

The fourth proportional to 87.11, 120.17 and 57.66 is: 79.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.11 : 120.17 = 57.66 : x
  2. Step 2: Convert to fraction form
    87.11/120.17 = 57.66/x
  3. Step 3: Cross multiply
    87.11x = 120.17 × 57.66
  4. Step 4: Simplify right side
    87.11x = 6,929.15
  5. Step 5: Solve for x
    x = 6,929.15/87.11
  6. Step 6: Final answer
    x = 79.54

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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.