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Finding the Fourth Proportional to 80.57, 120.17 and 69.63

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Solution

The fourth proportional to 80.57, 120.17 and 69.63 is: 103.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.57 : 120.17 = 69.63 : x
  2. Step 2: Convert to fraction form
    80.57/120.17 = 69.63/x
  3. Step 3: Cross multiply
    80.57x = 120.17 × 69.63
  4. Step 4: Simplify right side
    80.57x = 8,367.16
  5. Step 5: Solve for x
    x = 8,367.16/80.57
  6. Step 6: Final answer
    x = 103.85

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.