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Finding the Fourth Proportional to 80.10, 120.20 and 54.45

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Solution

The fourth proportional to 80.10, 120.20 and 54.45 is: 81.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.10 : 120.20 = 54.45 : x
  2. Step 2: Convert to fraction form
    80.10/120.20 = 54.45/x
  3. Step 3: Cross multiply
    80.10x = 120.20 × 54.45
  4. Step 4: Simplify right side
    80.10x = 6,544.89
  5. Step 5: Solve for x
    x = 6,544.89/80.10
  6. Step 6: Final answer
    x = 81.71

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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.