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Finding the Fourth Proportional to 121.11, 181.66 and 80.81

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Solution

The fourth proportional to 121.11, 181.66 and 80.81 is: 121.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    121.11 : 181.66 = 80.81 : x
  2. Step 2: Convert to fraction form
    121.11/181.66 = 80.81/x
  3. Step 3: Cross multiply
    121.11x = 181.66 × 80.81
  4. Step 4: Simplify right side
    121.11x = 14,679.94
  5. Step 5: Solve for x
    x = 14,679.94/121.11
  6. Step 6: Final answer
    x = 121.22

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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.