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Finding the Fourth Proportional to 87.24, 120.44 and 66.61

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Solution

The fourth proportional to 87.24, 120.44 and 66.61 is: 91.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.24 : 120.44 = 66.61 : x
  2. Step 2: Convert to fraction form
    87.24/120.44 = 66.61/x
  3. Step 3: Cross multiply
    87.24x = 120.44 × 66.61
  4. Step 4: Simplify right side
    87.24x = 8,021.77
  5. Step 5: Solve for x
    x = 8,021.77/87.24
  6. Step 6: Final answer
    x = 91.95

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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.