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Finding the Fourth Proportional to 80.29, 110.85 and 76.85

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Solution

The fourth proportional to 80.29, 110.85 and 76.85 is: 106.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.29 : 110.85 = 76.85 : x
  2. Step 2: Convert to fraction form
    80.29/110.85 = 76.85/x
  3. Step 3: Cross multiply
    80.29x = 110.85 × 76.85
  4. Step 4: Simplify right side
    80.29x = 8,518.82
  5. Step 5: Solve for x
    x = 8,518.82/80.29
  6. Step 6: Final answer
    x = 106.10

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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.