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Finding the Fourth Proportional to 83.85, 125.96 and 80.81

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Solution

The fourth proportional to 83.85, 125.96 and 80.81 is: 121.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    83.85 : 125.96 = 80.81 : x
  2. Step 2: Convert to fraction form
    83.85/125.96 = 80.81/x
  3. Step 3: Cross multiply
    83.85x = 125.96 × 80.81
  4. Step 4: Simplify right side
    83.85x = 10,178.74
  5. Step 5: Solve for x
    x = 10,178.74/83.85
  6. Step 6: Final answer
    x = 121.39

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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.