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Finding the Fourth Proportional to 80.11, 120.18 and 57.21

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Solution

The fourth proportional to 80.11, 120.18 and 57.21 is: 85.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.11 : 120.18 = 57.21 : x
  2. Step 2: Convert to fraction form
    80.11/120.18 = 57.21/x
  3. Step 3: Cross multiply
    80.11x = 120.18 × 57.21
  4. Step 4: Simplify right side
    80.11x = 6,875.50
  5. Step 5: Solve for x
    x = 6,875.50/80.11
  6. Step 6: Final answer
    x = 85.83

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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.