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Finding the Fourth Proportional to 217.89, 326.61 and 80.85

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Solution

The fourth proportional to 217.89, 326.61 and 80.85 is: 121.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    217.89 : 326.61 = 80.85 : x
  2. Step 2: Convert to fraction form
    217.89/326.61 = 80.85/x
  3. Step 3: Cross multiply
    217.89x = 326.61 × 80.85
  4. Step 4: Simplify right side
    217.89x = 26,406.42
  5. Step 5: Solve for x
    x = 26,406.42/217.89
  6. Step 6: Final answer
    x = 121.19

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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.