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Finding the Fourth Proportional to 80.76, 120.23 and 79.85

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Solution

The fourth proportional to 80.76, 120.23 and 79.85 is: 118.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.76 : 120.23 = 79.85 : x
  2. Step 2: Convert to fraction form
    80.76/120.23 = 79.85/x
  3. Step 3: Cross multiply
    80.76x = 120.23 × 79.85
  4. Step 4: Simplify right side
    80.76x = 9,599.37
  5. Step 5: Solve for x
    x = 9,599.37/80.76
  6. Step 6: Final answer
    x = 118.86

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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.