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Finding the Fourth Proportional to 121.29, 166.89 and 120.61

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Solution

The fourth proportional to 121.29, 166.89 and 120.61 is: 165.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    121.29 : 166.89 = 120.61 : x
  2. Step 2: Convert to fraction form
    121.29/166.89 = 120.61/x
  3. Step 3: Cross multiply
    121.29x = 166.89 × 120.61
  4. Step 4: Simplify right side
    121.29x = 20,128.60
  5. Step 5: Solve for x
    x = 20,128.60/121.29
  6. Step 6: Final answer
    x = 165.95

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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.