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Finding the Fourth Proportional to 80.82, 120.81 and 70.11

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Solution

The fourth proportional to 80.82, 120.81 and 70.11 is: 104.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.82 : 120.81 = 70.11 : x
  2. Step 2: Convert to fraction form
    80.82/120.81 = 70.11/x
  3. Step 3: Cross multiply
    80.82x = 120.81 × 70.11
  4. Step 4: Simplify right side
    80.82x = 8,469.64
  5. Step 5: Solve for x
    x = 8,469.64/80.82
  6. Step 6: Final answer
    x = 104.80

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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.